Compound and organic photoelectric device, image sensor and electronic device including the same

ABSTRACT

Example embodiments provide a compound of Chemical Formula 1, and an organic photoelectric device, an image sensor, and an electronic device including the same.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Korean Patent Application No.10-2016-0042427 filed in the Korean Intellectual Property Office on Apr.6, 2016, and all the benefits accruing therefrom under 35 U.S.C. § 119,the content of which is incorporated herein in its entirety byreference.

BACKGROUND 1. Field

Example embodiments relate to a compound and an organic photoelectricdevice, an image sensor, and an electronic device including the same.

2. Description of the Related Art

A photoelectric device may convert light into an electrical signal usingphotoelectric effects. A photoelectric device may include a photodiode,a phototransistor, etc. A photoelectronic device may be applied to animage sensor, a solar cell, an organic light emitting diode, etc.

An image sensor including a photodiode requires relatively highresolution and thus a smaller pixel. At present, a silicon photodiode iswidely used. In some cases, a silicon photodiode exhibits a problem ofdeteriorated sensitivity because of a relatively small absorption areadue to relatively small pixels. Accordingly, an organic material that iscapable of replacing silicon has been researched.

An organic material has a relatively high extinction coefficient andselectively absorbs light in a particular wavelength region depending ona molecular structure, and thus may simultaneously replace a photodiodeand a color filter and resultantly improve sensitivity and contribute torelatively high integration.

SUMMARY

Example embodiments provide a compound that selectively absorbs light ina green wavelength region.

Example embodiments also provide an organic photoelectric device capableof selectively absorbing light in a green wavelength region andimproving efficiency.

Example embodiments also provide an image sensor including the organicphotoelectric device.

Example embodiments also provide an electronic device including theimage sensor.

According to example embodiments, a compound represented by ChemicalFormula 1.

In Chemical Formula 1,

Ar is selected from a substituted or unsubstituted 5-membered aromaticring, a substituted or unsubstituted 6-membered aromatic ring, and acondensed ring of two or more of the foregoing rings,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹ to R³ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, and

each of Ar¹ and Ar² are independently selected from a substituted orunsubstituted C₆ to C₃₀ aryl group, and a substituted or unsubstitutedC₃ to C₃₀ heteroaryl group, provided that at least one of Ar¹ and Ar² isa heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

In Chemical Formula 1, at least one of Ar¹ and Ar² may selected from asubstituted or unsubstituted pyrrolyl group, a substituted orunsubstituted prazolyl group, a substituted or unsubstituted midazolylgroup, a substituted or unsubstituted oxazolyl group, a substituted orunsubstituted isoxazolyl group, a substituted or unsubstituted thiazolylgroup, a substituted or unsubstituted isothiazolyl group, a substitutedor unsubstituted pyridinyl group, a substituted or unsubstitutedpyridazinyl group, a substituted or unsubstituted pyrimidinyl group, asubstituted or unsubstituted pyrazinyl group, a substituted orunsubstituted indolyl group, a substituted or unsubstituted quinolinylgroup, a substituted or unsubstituted isoquinolinyl group, a substitutedor unsubstituted naphthyridinyl group, a substituted or unsubstitutedcinnolinyl group, a substituted or unsubstituted quinazolinyl group, asubstituted or unsubstituted phthalazinyl group, a substituted orunsubstituted benzotriazinyl group, a substituted or unsubstitutedpyridopyrazinyl group, a substituted or unsubstituted pyridopyrimidinylgroup, a substituted or unsubstituted pyridopyridazinyl group, asubstituted or unsubstituted thienyl group, a substituted orunsubstituted benzothienyl group, a substituted or unsubstitutedselenophenyl group, and a substituted or unsubstituted benzoselenophenylgroup, and the functional groups may include at least one nitrogen (N)at an ortho position with respect to a bond with the nitrogen (N).

The compound represented by Chemical Formula 1 may be represented byChemical Formula 2.

In Chemical Formula 2,

Ar is selected from a substituted or unsubstituted 5-membered aromaticring, a substituted or unsubstituted 6-membered aromatic ring, and acondensed ring of two or more of the foregoing rings,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹ to R³ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is a heteroaryl group including at least one nitrogen (N) at anortho position with respect to a bond with the nitrogen (N) of ChemicalFormula 2.

In Chemical Formula 2, Ar′¹ may be selected from a substituted orunsubstituted pyrrolyl group, a substituted or unsubstituted pyrazolylgroup, a substituted or unsubstituted imidazolyl group, a substituted orunsubstituted oxazolyl group, a substituted or unsubstituted isoxazolylgroup, a substituted or unsubstituted thiazolyl group, a substituted orunsubstituted isothiazolyl group, a substituted or unsubstitutedpyridinyl group, a substituted or unsubstituted pyridazinyl group, asubstituted or unsubstituted pyrimidinyl group, a substituted orunsubstituted pyrazinyl group, a substituted or unsubstituted indolylgroup, a substituted or unsubstituted quinolinyl group, a substituted orunsubstituted isoquinolinyl group, a substituted or unsubstitutednaphthyridinyl group, a substituted or unsubstituted cinnolinyl group, asubstituted or unsubstituted quinazolinyl group, a substituted orunsubstituted phthalazinyl group, a substituted or unsubstitutedbenzotriazinyl group, a substituted or unsubstituted pyridopyrazinylgroup, a substituted or unsubstituted pyridopyrimidinyl group, asubstituted or unsubstituted pyridopyridazinyl group, a substituted orunsubstituted thienyl group, a substituted or unsubstituted benzothienylgroup, a substituted or unsubstituted selenophenyl group, and asubstituted or unsubstituted benzoselenophenyl group, and the functionalgroups may include at least one nitrogen (N) at an ortho position withrespect to a bond with the nitrogen (N).

The compound represented by Chemical Formula 1 may be represented by oneof Chemical Formulae 3-1 to 3-6.

In Chemical Formulae 3-1 to 3-6,

Ar is selected from a substituted or unsubstituted 5-membered aromaticring, a substituted or unsubstituted 6-membered aromatic ring, and acondensed ring of two or more of the foregoing rings,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹ to R³ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof,

each of R^(4a) to R^(4e) or R^(5a) to R^(5d) are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C₃ to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof, oroptionally two adjacent groups of R^(4a) to R^(4e) are linked with eachother to provide a 5-membered aromatic ring or a 6-membered aromaticring and optionally two adjacent groups of R^(5a) to R^(5d) are linkedwith each other to provide a 5-membered aromatic ring or a 6-memberedaromatic ring, and

each of a and b are independently an integer of 0 or 1.

In Chemical Formulae 1, 2, and 3-1 to 3-6, a ring group represented byAr and bound to a methine group may be represented by Chemical Formula4.

In Chemical Formula 4,

Ar′ is selected from a substituted or unsubstituted 5-membered aromaticring, a substituted or unsubstituted 6-membered aromatic ring, and acondensed ring of two or more of the foregoing rings, and

Z¹ is O or CR^(b)R^(c), wherein each of R^(b) and R^(c) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₁₀ alkyl group, a cyano group, or a cyano-containing group, providedthat at least one of R^(b) and R^(c) is a cyano group or acyano-containing group.

In Chemical Formulae 1, 2, and 3-1 to 3-6, the ring group represented byAr and bound to a methine group may be a ring group represented by oneof Chemical Formulae 5-1 to 5-4.

In Chemical Formula 5-1,

Z¹ is O or CR^(b)R^(c), wherein each of R^(b) and R^(c) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₁₀ alkyl group, a cyano group, or a cyano-containing group, providedthat at least one of R^(b) and R^(c) is a cyano group or acyano-containing group,

Y¹ is selected from N and CR^(d), wherein R^(d) is selected fromhydrogen and a substituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹¹, R¹², R¹³, R¹⁴, and R¹⁵ is hydrogen, a substituted orunsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, or R¹² and R¹³ are independently linked with eachother to provide an aromatic ring and R¹⁴ and R¹⁵ are independentlylinked with each other to provide an aromatic ring,

m1 is 0 or 1, and

n is 0 or 1.

In Chemical Formula 5-2,

Y² is selected from O, S, Se, Te, and C(R^(e))(CN), wherein R^(e) isselected from hydrogen, a cyano group (—CN), and a C₁ to C₁₀ alkylgroup, and

each of R¹⁶ and R¹⁷ are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), and a combination thereof.

In Chemical Formula 5-3,

each of R¹⁸ to R²⁰ are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), a cyano-containing group, and acombination thereof.

In Chemical Formula 5-4,

Y² is selected from O, S, Se, Te, and C(R^(e))(CN) wherein R^(e) isselected from hydrogen, a cyano group (—CN), and a C₁ to C₁₀ alkylgroup,

Y³ is selected from O, S, Se, and Te,

Y⁴ is N or NR^(f),

Y⁵ is selected from CR^(g), C═O, C═S, C═(CR^(h))(CN), and ChemicalFormula 5-4,

at least one of Y² and Y⁵ is C═O,

each of R^(f), R^(g), and R^(h) are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C4 toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, and

optionally Y⁴ and Y⁵ are linked with each other to provide a fused ringwith a Y⁴—Y⁵-containing pentagonal ring of Chemical Formula 5-4.

The compound may be a compound represented by one of Chemical Formulae6-1 to 6-4.

In Chemical Formula 6-1,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹ to R³ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof,

Z¹ is O or CR^(b)R^(c), wherein each of R^(b) and R^(c) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₁₀ alkyl group, a cyano group, or a cyano-containing group, providedthat at least one of R^(b) and R^(c) is a cyano group or acyano-containing group,

Y¹ is selected from N and CR^(d), wherein R^(d) is selected fromhydrogen and a substituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹¹, R¹², R¹³, R¹⁴, and R¹⁵ are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C4 toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof or R¹² and R¹³ are independently linkedwith each other to provide an aromatic ring and R¹⁴ and R¹⁵ areindependently linked with each other to provide an aromatic ring,

m1 is 0 or 1,

n is 0 or 1,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

In Chemical Formula 6-2,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

Y² is selected from O, S, Se, Te, and C(R^(e))(CN) wherein R^(e) isselected from hydrogen, a cyano group (—CN), and a C₁ to C₁₀ alkylgroup,

each of R¹, R², R³, R¹⁶, and R¹⁷ are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C4 toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

In Chemical Formula 6-3,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹, R², R³, R¹⁸, R¹⁹, and R²⁰ are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C4 toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

Y² is selected from O, S, Se, Te, and C(R^(e))(CN) wherein R^(e) isselected from hydrogen, a cyano group (—CN), and a C₁ to C₁₀ alkylgroup,

Y³ is selected from O, S, Se, and Te,

Y⁴ is N or NR^(f),

Y⁵ is selected from CR^(g), C═O, C═S, C═(CR^(h))(CN), and ChemicalFormula 5-4,

at least one of Y² and Y⁵ is C═O,

each of R¹, R², R³, R^(f), R^(g), and R^(h) are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C4 toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof,

optionally Y⁴ and Y⁵ are linked with each other to provide a fused ringwith a Y⁴—Y⁵-containing pentagonal ring of Chemical Formula 5-4,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

The compound may have a maximum absorption wavelength (λ_(max)) in awavelength region of greater than or equal to about 510 nm and less thanabout 560 nm, for example about 520 nm to about 555 nm in a thin filmstate.

The compound may exhibit a light absorption curve having a full width athalf maximum (FWHM) of about 50 nm to about 110 nm, in a thin filmstate.

According to example embodiments, an organic photoelectric deviceincludes a first electrode and a second electrode facing each other andan active layer between the first electrode and the second electrode andincluding the compound represented by Chemical Formula 1.

The compound may be a compound represented by Chemical Formula 2 orChemical Formula 3.

The ring group represented by Ar and bound to a methine group may berepresented by Chemical Formula 4.

The active layer may have a maximum absorption wavelength (λ_(max)) in awavelength region of greater than or equal to about 510 nm and less thanabout 560 nm, for example about 520 nm to about 555 nm.

The active layer may exhibit a light absorption curve having a fullwidth at half maximum (FWHM) of about 50 nm to about 110 nm.

The active layer may have an absorption coefficient of greater than orequal to about 5.5×10⁴ cm⁻¹, for example about 5.8×10⁴ cm⁻¹ to about10×10⁴ cm⁻¹ when including the compound of Chemical Formula 1 and C60 ina volume ratio of about 0.9:1 to about 1.1:1.

According to example embodiments, an image sensor includes the organicphotoelectric device.

The image sensor may include a semiconductor substrate integrated with aplurality of first photo-sensing devices configured to sense light in ablue wavelength region and a plurality of second photo-sensing devicesconfigured to sense light in a red wavelength region, and the organicphotoelectric device on the semiconductor substrate and selectivelysensing light in a green wavelength region.

The first photo-sensing device and the second photo-sensing device maybe stacked in a vertical direction in the semiconductor substrate.

The image sensor may further include a color filter layer between thesemiconductor substrate and the organic photoelectric device, andincluding a blue filter configured to selectively absorb light in a bluewavelength region and a red filter selectively absorbing light in a redwavelength region.

The image sensor may include a green photoelectric device of the organicphotoelectric device, a blue photoelectric device configured toselectively absorb light in a blue wavelength region, and a redphotoelectric device configured to selectively absorb light in a redwavelength region that are stacked.

The image sensor may have a color difference (ΔE*ab) of less than about4.0.

According to example embodiments, an electronic device includes theimage sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing an organic photoelectric deviceaccording to example embodiments,

FIG. 2 is a cross-sectional view showing an organic photoelectric deviceaccording to example embodiments,

FIG. 3 is a schematic top plan view showing an organic CMOS image sensoraccording to example embodiments,

FIG. 4 is a cross-sectional view showing the organic CMOS image sensorof FIG. 3,

FIG. 5 is a schematic cross-sectional view showing an organic CMOS imagesensor according to example embodiments,

FIG. 6 is a schematic cross-sectional view showing an organic CMOS imagesensor according to example embodiments, and

FIG. 7 is a schematic view showing an organic CMOS image sensoraccording to example embodiments.

DETAILED DESCRIPTION

Example embodiments will hereinafter be described in detail, and may beeasily performed by those who have common knowledge in the related art.However, this disclosure may be embodied in many different forms and isnot to be construed as limited to the example embodiments set forthherein.

In the drawings, the thickness of layers, films, panels, regions, etc.,are exaggerated for clarity. Like reference numerals designate likeelements throughout the specification. It will be understood that whenan element such as a layer, film, region, or substrate is referred to asbeing “on” another element, it can be directly on the other element orintervening elements may also be present. In contrast, when an elementis referred to as being “directly on” another element, there are nointervening elements present.

In the drawings, parts having no relationship with the description areomitted for clarity of the embodiments, and the same or similarconstituent elements are indicated by the same reference numeralsthroughout the specification.

As used herein, when specific definition is not otherwise provided, theterm “substituted” refers to one substituted with a substituent selectedfrom a halogen atom (F, Cl, Br or I), a hydroxy group, a nitro group, acyano group, an amino group, an azido group, an amidino group, ahydrazino group, a hydrazono group, a carbonyl group, a carbamyl group,a thiol group, an ester group, a carboxyl group or a salt thereof, asulfonic acid group or a salt thereof, phosphoric acid group or a saltthereof, a C₁ to C₂₀ alkyl group, a C₁ to C₂₀ alkoxy group, a C₂ to C₂₀alkenyl group, a C₂ to C₂₀ alkynyl group, a C₆ to C₃₀ aryl group, a C₇to C₃₀ arylalkyl group, a C₂ to C₂₀ heteroaryl group, a C₃ to C₂₀heteroarylalkyl group, a C₃ to C₃₀ cycloalkyl group, a C₃ to C₁₅cycloalkenyl group, a C₆ to C₁₅ cycloalkynyl group, a C₂ to C₂₀heterocycloalkyl group, and a combination thereof, instead of hydrogenof a compound.

As used herein, when specific definition is not otherwise provided, theterm “hetero” refers to one including 1 to 3 heteroatoms selected fromN, O, S, P, and Si.

As used herein, the term “alkyl group” for example refers to a methylgroup, an ethyl group, a propyl group, an isopropyl group, a n-butylgroup, an isobutyl group, a t-butyl group, a pentyl group, a hexylgroup, etc.

As used herein, the term “cycloalkyl group” for example refers to acyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexylgroup, etc.

As used herein, the term “aryl group” refers to a substituent includingall element of the cycle having p-orbitals which form conjugation, andmay be a monocyclic, polycyclic or fused ring polycyclic (i.e., ringssharing adjacent pairs of carbon atoms) functional group.

As used herein, when a definition is not otherwise provided, the term“cyano-containing group” refers to a monovalent group such as a C₁ toC₃₀ alkyl group, a C2 to C₃₀ alkenyl group, or a C2 to C₃₀ alkynyl groupwhere at least one hydrogen is substituted with a cyano group. Thecyano-containing group also refers to a divalent group such as adicyanoalkenyl group represented by═CR^(x′)—(CR^(x)R^(y))_(p)—CR^(y′)(CN)₂ wherein each of R^(x), R^(y),R^(x′), and R^(y′) are independently hydrogen or a C₁ to C₁₀ alkyl groupand p is an integer of 0 to 10. Specific examples of thecyano-containing group may be a dicyanomethyl group, a dicyanovinylgroup, a cyanoethynyl group, etc.

As used herein, when a definition is not otherwise provided, the term“combination thereof” refers to at least two substituents bound to eachother by a single bond or a C₁ to C₁₀ alkylene group, or at least twofused substituents.

As used herein, the term “5-membered aromatic ring” refers to a5-membered cyclic group (e.g., C₅ aryl group) having a conjugationstructure or a 5-membered heterocyclic group (e.g., C₂ to C₄ heteroarylgroup) having a conjugation structure. As used herein, the term“6-membered aromatic ring” refers to a 6-membered cyclic group (e.g., C₆aryl group) having a conjugation structure or a 6-membered heterocyclicgroup (e.g., C₂ to C₅ heteroaryl group) having a conjugation structure,but is not limited thereto. The aromatic ring may include the 5-memberedaromatic ring or the 6-membered aromatic ring, but is not limitedthereto.

Hereinafter, a compound according to example embodiments is described.The compound is represented by Chemical Formula 1.

In Chemical Formula 1,

Ar is selected from a substituted or unsubstituted 5-membered aromaticring, a substituted or unsubstituted 6-membered aromatic ring, and acondensed ring of two or more of the foregoing rings,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹ to R³ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C6 to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof,

each of Ar¹ and Ar² are independently selected from a substituted orunsubstituted C6 to C₃₀ aryl group, and a substituted or unsubstitutedC₃ to C₃₀ heteroaryl group, provided that at least one of Ar¹ and Ar² isa heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N) of ChemicalFormula 1.

The compound represented by Chemical Formula 1 includes electron donormoiety of aryl amine (—N(Ar¹)(Ar²)), a linker including an X¹-containing5-membered ring and a methine group, and an electron acceptor moietyrepresented by Ar.

Each of Ar¹ and Ar² are a substituted or unsubstituted C₆ to C₃₀ arylgroup or a substituted or unsubstituted C₃ to C₃₀ heteroaryl group,wherein aromatic rings are present alone or fused together,specifically, a substituted or unsubstituted C₆ to C₂₀ aryl group, andfor example, a substituted or unsubstituted C₈ to C₂₀ aryl group or asubstituted or unsubstituted C₃ to C₂₀ heteroaryl group. In other words,a single bond between the aromatic rings or a conjugation structure ofthe aromatic groups connected through another linking group is broken,failing in providing a sufficient conjugation length. In addition, whenAr¹ and Ar² are not the aromatic groups but alkyl groups or connectedeach other and form a N-containing aliphatic cyclic group, a lightabsorption curved line has so wide a full width at half maximum (FWHM)that absorption selectivity of a green wavelength region may bedeteriorated.

At least either one of Ar¹ and Ar² is a heteroaryl group including atleast one nitrogen (N) at an ortho position with respect to a bond withthe nitrogen (N) of Chemical Formula 1. At least one nitrogen (N) atomat the ortho position with respect to a bond with the nitrogen (N) mayincrease an intramolecular interaction between X¹ present in the linkerand oxygen (O) of a carbonyl group present in the electron acceptormoiety and thus improve absorption intensity at a particular wavelength.When the heteroatom is present at a meta or para position with respectto a bond with the nitrogen (N), the intramolecular interaction may notbe sufficient, and thus sufficient absorbance may not be obtained.

In example embodiments, at least one of Ar¹ and Ar² may be a substitutedor unsubstituted pyrrolyl group, a substituted or unsubstituted prazolylgroup, a substituted or unsubstituted midazolyl group, a substituted orunsubstituted oxazolyl group, a substituted or unsubstituted isoxazolylgroup, a substituted or unsubstituted thiazolyl group, a substituted orunsubstituted isothiazolyl group, a substituted or unsubstitutedpyridinyl group, a substituted or unsubstituted pyridazinyl group, asubstituted or unsubstituted pyrimidinyl group, a substituted orunsubstituted pyrazinyl group, a substituted or unsubstituted indolylgroup, a substituted or unsubstituted a substituted or unsubstitutedquinolinyl group, a substituted or unsubstituted isoquinolinyl group, asubstituted or unsubstituted naphthyridinyl group, a substituted orunsubstituted cinnolinyl group, a substituted or unsubstitutedquinazolinyl group, a substituted or unsubstituted phthalazinyl group, asubstituted or unsubstituted benzotriazinyl group, a substituted orunsubstituted pyridopyrazinyl group, a substituted or unsubstitutedpyridopyrimidinyl group, a substituted or unsubstitutedpyridopyridazinyl group, a substituted or unsubstituted thienyl group, asubstituted or unsubstituted benzothienyl group, a substituted orunsubstituted selenophenyl group, and a substituted or unsubstitutedbenzoselenophenyl group, and the functional groups may include at leastone nitrogen (N) at an ortho position with respect to a bond with thenitrogen (N).

In example embodiments, one of Ar¹ and Ar² may be a substituted orunsubstituted phenyl group or a substituted or unsubstituted naphthylgroup, and the other of Ar¹ and Ar² may be a substituted orunsubstituted pyrrolyl group, a substituted or unsubstituted pyrazolylgroup, a substituted or unsubstituted imidazolyl group, a substituted orunsubstituted oxazolyl group, a substituted or unsubstituted isoxazolylgroup, a substituted or unsubstituted thiazolyl group, a substituted orunsubstituted isothiazolyl group, a substituted or unsubstitutedpyridinyl group, a substituted or unsubstituted pyridazinyl group, asubstituted or unsubstituted pyrimidinyl group, a substituted orunsubstituted pyrazinyl group, a substituted or unsubstituted indolylgroup, a substituted or unsubstituted quinolinyl group, a substituted orunsubstituted isoquinolinyl group, a substituted or unsubstitutednaphthyridinyl group, a substituted or unsubstituted cinnolinyl group, asubstituted or unsubstituted quinazolinyl group, a substituted orunsubstituted phthalazinyl group, a substituted or unsubstitutedbenzotriazinyl group, a substituted or unsubstituted pyridopyrazinylgroup, a substituted or unsubstituted pyridopyrimidinyl group, asubstituted or unsubstituted pyridopyridazinyl group, a substituted orunsubstituted thienyl group, a substituted or unsubstituted benzothienylgroup, a substituted or unsubstituted selenophenyl group, and asubstituted or unsubstituted benzoselenophenyl group, and the functionalgroups may include at least one nitrogen (N) at an ortho position withrespect to a bond with the nitrogen (N).

The compound represented by Chemical Formula 1 may be represented byChemical Formula 2.

In Chemical Formula 2,

Ar is selected from a substituted or unsubstituted 5-membered aromaticring, a substituted or unsubstituted 6-membered aromatic ring, and acondensed ring of two or more of the foregoing rings,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹ to R³ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

In Chemical Formula 2, Ar′¹ may be selected from a substituted orunsubstituted pyrrolyl group, a substituted or unsubstituted pyrazolylgroup, a substituted or unsubstituted imidazolyl group, a substituted orunsubstituted oxazolyl group, a substituted or unsubstituted isoxazolylgroup, a substituted or unsubstituted thiazolyl group, a substituted orunsubstituted isothiazolyl group, a substituted or unsubstitutedpyridinyl group, a substituted or unsubstituted pyridazinyl group, asubstituted or unsubstituted pyrimidinyl group, a substituted orunsubstituted pyrazinyl group, a substituted or unsubstituted indolylgroup, a substituted or unsubstituted quinolinyl group, a substituted orunsubstituted isoquinolinyl group, a substituted or unsubstitutednaphthyridinyl group, a substituted or unsubstituted cinnolinyl group, asubstituted or unsubstituted quinazolinyl group, a substituted orunsubstituted phthalazinyl group, a substituted or unsubstitutedbenzotriazinyl group, a substituted or unsubstituted pyridopyrazinylgroup, a substituted or unsubstituted pyridopyrimidinyl group, asubstituted or unsubstituted pyridopyridazinyl group, a substituted orunsubstituted thienyl group, a substituted or unsubstituted benzothienylgroup, a substituted or unsubstituted selenophenyl group, and asubstituted or unsubstituted benzoselenophenyl group.

The compound represented by Chemical Formula 1 may be represented by oneof Chemical Formulae 3-1 to 3-6.

In Chemical Formulae 3-1 to 3-6,

Ar is selected from a substituted or unsubstituted 5-membered aromaticring, a substituted or unsubstituted 6-membered aromatic ring, and acondensed ring of two or more of the foregoing rings,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹ to R³ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof,

each of R^(4a) to R^(4e) or R^(5a) to R^(5d) are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C₃ to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof, oroptionally two adjacent groups of R^(4a) to R^(4e) are linked with eachother to provide a 5-membered aromatic ring or a 6-membered aromaticring and optionally two adjacent groups of R^(5a) to R^(5d) are linkedwith each other to provide a 5-membered aromatic ring or a 6-memberedaromatic ring, and

each of a and b are independently an integer of 0 or 1.

In Chemical Formula 1, a Chemical Formula 2, and Chemical Formulae 3-1to 3-6, the ring group represented by Ar is an electron acceptor moietythat includes at least one carbonyl group.

For example, in Chemical Formula 1, Chemical Formula 2, and ChemicalFormulae 3-1 to 3-6, the ring group represented by Ar and bound to amethine group may include at least one carbonyl group.

For example, in Chemical Formulae 1, 2, and 3-1 to 3-6, the ring grouprepresented by Ar and bound to a methine group may include at least onecarbonyl group and at least one cyano-containing moiety.

In Chemical Formulae 1, 2, and 3-1 to 3-6, the ring group represented byAr and bound to a methine group may be represented by Chemical Formula4.

In Chemical Formula 4,

Ar′ is selected from a substituted or unsubstituted 5-membered aromaticring, a substituted or unsubstituted 6-membered aromatic ring, and acondensed ring of two or more of the foregoing rings,

Z¹ is O or CR^(b)R^(c), wherein each of R^(b) and R^(c) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₁₀ alkyl group, a cyano group, or a cyano-containing group, providedthat at least one of R^(b) and R^(c) is a cyano group or acyano-containing group.

For example, the ring group represented by Ar and bound to a methinegroup may be a condensed ring of a substituted or unsubstituted5-membered aromatic ring and a substituted or unsubstituted 6-memberedaromatic ring.

In Chemical Formula 1, Chemical Formula 2, and Chemical Formulae 3-1 to3-6, the ring group represented by Ar and bound to a methine group maybe a ring group represented by one of Chemical Formulae 5-1 to 5-4.

In Chemical Formula 5-1,

Z¹ is O or CR^(b)R^(c), wherein each of R^(b) and R^(c) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₁₀ alkyl group, a cyano group, or a cyano-containing group, providedthat at least one of R^(b) and R^(c) is a cyano group or acyano-containing group,

Y¹ is selected from N and CR^(d), wherein R^(d) is selected fromhydrogen and a substituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹¹, R¹², R¹³, R¹⁴, and R¹⁵ are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C4 to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof, or R¹² andR¹³ are independently linked with each other to provide an aromatic ringand R¹⁴ and R¹⁵ are independently linked with each other to provide anaromatic ring,

m1 is 0 or 1, and

n is 0 or 1.

In Chemical Formula 5-2,

Y² is selected from O, S, Se, Te, and C(R^(e))(CN) wherein R^(e) isselected from hydrogen, a cyano group (—CN), and a C₁ to C₁₀ alkylgroup, and

each of R¹⁶ and R¹⁷ are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), and a combination thereof.

In Chemical Formula 5-3,

each of R¹⁸ to R²⁰ are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), a cyano-containing group, and acombination thereof.

In Chemical Formula 5-4,

Y² is selected from O, S, Se, Te, and C(R^(e))(CN) wherein R^(e) isselected from hydrogen, a cyano group (—CN), and a C₁ to C₁₀ alkylgroup,

Y³ is selected from O, S, Se, and Te,

Y⁴ is N or NR^(f),

Y⁵ is selected from CR^(g), C═O, C═S, C═(CR^(h))(CN), and ChemicalFormula 5-4,

at least one of Y² and Y⁵ is C═O,

each of R^(f), R^(g), and R^(h) are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C4 toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, and

optionally Y⁴ and Y⁵ are linked with each other to provide a fused ringwith a Y⁴—Y⁵-containing pentagonal ring of Chemical Formula 5-4. Forexample, the fused ring with the Y⁴—Y⁵-containing pentagonal ring may bea benzimidazole or indole ring.

The ring group represented by Chemical Formula 5-1 may be, for example aring group represented by Chemical Formula 5-1-1, 5-1-2, or 5-1-3.

In Chemical Formulae 5-1-1, 5-1-2, and 5-1-3, Y¹, R¹¹, m1, and n are thesame as in Chemical Formula 5-1,

each of R^(12a), R^(12b), R^(12c), and R^(14a) are independentlyselected from hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkylgroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C₄ to C₃₀ heteroaryl group, a halogen, acyano group (—CN), a cyano-containing group, and a combination thereof,

each of m2, m3, m4, and m5 are independently an integer ranging from 0to 4, and

each of Ph1 and Ph2 denote a fused phenylene ring. One of Ph1 and Ph2may be optionally omitted.

The ring group represented by Chemical Formula 5-2 may be, for example aring group represented by Chemical Formula 5-2-1 or 5-2-2.

In Chemical Formulae 5-2-1 and 5-2-2, R¹⁶ and R¹⁷ are the same as inChemical Formula 5-2.

The ring group represented by Chemical Formula 5-3 may be, for example aring group represented by Chemical Formula 5-3-1 or 5-3-2.

In Chemical Formulae 5-3-1 and 5-3-2, R¹⁸ to R²⁰ are the same as inChemical Formula 5-3.

The ring group represented by Chemical Formula 5-4 may be, for example aring group represented by Chemical Formula 5-4-1, 5-4-2, 5-4-3, or5-4-4.

In Chemical Formulae 5-4-1, 5-4-2, 5-4-3, and 5-4-4, Y³ and R^(f) arethe same as in Chemical Formula 5-4, and

in Chemical Formula 5-4-4, each of R^(i) and R^(j) are independentlyselected from hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkylgroup, a substituted or unsubstituted C₁ to C₃₀ alkoxy group, asubstituted or unsubstituted C6 to C₃₀ aryl group, a substituted orunsubstituted C₄ to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof, oroptionally R^(i) and R^(j) are linked with each other to provide a fusedring. The fused ring may be a 5-membered or 6-membered aromatic ring ora hetero aromatic ring.

The compound may be a compound represented by one of Chemical Formulae6-1 to 6-4.

In Chemical Formula 6-1,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹ to R³ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C6 to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof,

Z¹ is O or CR^(b)R^(c), wherein each of R^(b) and R^(c) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₁₀ alkyl group, a cyano group, or a cyano-containing group, providedthat at least one of R^(b) and R^(c) is a cyano group or acyano-containing group,

Y¹ is selected from N and CR^(d), wherein R^(d) is selected fromhydrogen and a substituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹¹, R¹², R¹³, R¹⁴, and R¹⁵ are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C6 to C₃₀ aryl group, a substituted or unsubstituted C₄ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or R¹² and R¹³ are independentlylinked with each other to provide an aromatic ring and R¹⁴ and R¹⁵ areindependently linked with each other to provide an aromatic ring,

m1 is 0 or 1,

n is 0 or 1,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C6 to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

In Chemical Formula 6-2,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

Y² is selected from O, S, Se, Te, and C(R^(e))(CN) wherein R^(e) isselected from hydrogen, a cyano group (—CN), and a C₁ to C₁₀ alkylgroup,

each of R¹, R², R³, R¹⁶, and R¹⁷ are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C6 to C₃₀ aryl group, a substituted or unsubstituted C₄ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C6 to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

In Chemical Formula 6-3,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

each of R¹, R², R³, R¹⁸, R¹⁹, and R²⁰ are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C6 to C₃₀ aryl group, a substituted or unsubstituted C₄ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C6 to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).

In Chemical Formula 6-4,

X¹ is selected from Se, Te, O, NR^(a), S(═O), S(═O)₂, and SiR^(b)R^(c),wherein each of R^(a), R^(b), and R^(c) are selected from hydrogen and asubstituted or unsubstituted C₁ to C₁₀ alkyl group,

Y² is selected from O, S, Se, Te, and C(R^(e))(CN) wherein R^(e) isselected from hydrogen, a cyano group (—CN), and a C₁ to C₁₀ alkylgroup,

Y³ is selected from O, S, Se, and Te,

Y⁴ is N or NR^(f),

Y⁵ is selected from CR^(g), C═O, C═S, C═(CR^(h))(CN), and ChemicalFormula 5-4,

at least one of Y² and Y⁵ is C═O,

each of R¹, R², R³, R^(f), R^(g), and R^(h) are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₄ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof,

optionally Y⁴ and Y⁵ are linked with each other to provide a fused ringwith a Y⁴—Y⁵-containing pentagonal ring of Chemical Formula 5-4,

each of R^(4a) to R^(4e) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring,

a is an integer of 0 or 1,

X² is nitrogen (N), and

Ar′¹ is a heteroaryl group including at least one nitrogen (N) at anortho position with respect to a bond with the nitrogen (N).

The compound of Chemical Formula 1 may be, for example a compoundrepresented by Chemical Formulae 7-1, 7-2, 7-3, and 7-4 but is notlimited thereto.

In Chemical Formula 7-1,

hydrogen of each aromatic ring may be replaced by a substituent selectedfrom a substituted or unsubstituted C₁ to C₃₀ alkyl group, a substitutedor unsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstitutedC₆ to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀heteroaryl group, a halogen (F, Cl, Br or I), a cyano group (—CN), acyano-containing group, and a combination thereof.

In Chemical Formula 7-2,

R¹⁶ and R¹⁷ are the same as in Chemical Formula 5-2, and hydrogen ofeach aromatic ring may be replaced by a substituent selected from asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen (F, Cl, Br or I), a cyano group (—CN), acyano-containing group, and a combination thereof.

In Chemical Formula 7-3,

each of R¹⁸, R¹⁹, and R²⁰ are the same as in Chemical Formula 5-3, andhydrogen of each aromatic ring may be replaced by a substituent selectedfrom a substituted or unsubstituted C₁ to C₃₀ alkyl group, a substitutedor unsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstitutedC₆ to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀heteroaryl group, a halogen (F, Cl, Br or I), a cyano group (—CN), acyano-containing group, and a combination thereof.

In Chemical Formula 7-4,

R^(f) is the same as in Chemical Formula 5-4, and hydrogen of eacharomatic ring may be replaced by a substituent selected from asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group (e.g., phenyl group), a substituted or unsubstitutedC₄ to C₃₀ heteroaryl group, a halogen (F, Cl, Br or I), a cyano group(—CN), a cyano-containing group, and a combination thereof.

The compound is a compound selectively absorbing light in a greenwavelength region, and may have a maximum absorption wavelength(λ_(max)) in a wavelength region of greater than or equal to about 510nm and less than about 560 nm, for example about 520 nm to about 555 nm,and thus may be usefully applicable to an active layer of aphotoelectric device. Particularly, when it has a maximum absorptionwavelength (λ_(max)) in a wavelength region of about 520 nm to about 555nm, an image sensor including the photoelectric device has reduced colordifference (ΔE*ab).

The compound may exhibit a light absorption curve having a full width athalf maximum (FWHM) of about 50 nm to about 110 nm, in a thin filmstate. Herein, the FWHM is a width of a wavelength corresponding to halfof a maximum absorption point. As used herein, when specific definitionis not otherwise provided, it may be defined by absorbance measured byUV-Vis spectroscopy. When the full width at half maximum (FWHM) iswithin the range, selectivity in a green wavelength region may beincreased. The thin film may be a thin film deposited under a vacuumcondition.

The compound may be formed into a thin film using a deposition method.The deposition method may provide a uniform thin film and have smallinclusion possibility of impurities into the thin film, but when thecompound has a lower melting point than a temperature for thedeposition, a product decomposed from the compound may be deposited andthus performance of a device may be deteriorated. Accordingly, thecompound desirably has a higher melting point than the depositiontemperature. The compound has, for example, greater than or equal toabout 10° C. higher melting point than the deposition temperature andthus may be desirably used for the deposition.

Because the compound works as a p-type semiconductor, the compound maybe appropriately used, as long as it has a higher LUMO level than ann-type semiconductor. For example, when the compound is mixed with ann-type material such as fullerene, the compound desirably has a higherLUMO level than 4.2 eV than the fullerene having a LUMO level of 4.2 eV.As for the appropriate HOMO-LUMO level of the compound, when thecompound has a HOMO level ranging from about 5.0 eV to about 5.8 eV andan energy bandgap ranging from about 1.9 eV to about 2.3 eV, the LUMOlevel of the compound is in a range of about 3.9 eV to about 2.7 eV. Thecompound having a HOMO level, an LUMO level, and an energy bandgapwithin the ranges may be used as a p-type semiconductor compoundeffectively absorbing light in a green wavelength region, and thus hashigh external quantum efficiency (EQE) and resultantly improvesphotoelectric conversion efficiency.

In example embodiments, in view of a thin film formation, a stablydepositable compound is desirable and thus the compound has a molecularweight of about 300 to about 1500. However, even though the compound hasa molecular weight out of the range, a depositable compound may be usedwithout limitation. In addition, when the compound is formed to form athin film using a coating process, a compound that is dissolved in asolvent and coated may be used without limitation.

The compound may be used as a p-type semiconductor compound.

Hereinafter, an organic photoelectric device including the compoundaccording to an example embodiment is described with reference todrawings.

FIG. 1 is a cross-sectional view showing an organic photoelectric deviceaccording to example embodiments.

Referring to FIG. 1, an organic photoelectric device 100 according toexample embodiments includes a first electrode 10 and a second electrode20, and an active layer 30 between the first electrode 10 and the secondelectrode 20.

One of the first electrode 10 and the second electrode 20 is an anodeand the other is a cathode. At least one of the first electrode 10 andthe second electrode 20 may be a light-transmitting electrode, and thelight-transmitting electrode may at least partially comprise, forexample, a transparent conductor including indium tin oxide (ITO) orindium zinc oxide (IZO), or a metal thin layer of a thin single layer ormultilayer. When one of the first electrode 10 and the second electrode20 is a non-light-transmitting electrode, the first electrode 10 and/orthe second electrode 20 may at least partially comprise, for example, anopaque conductor including aluminum (Al).

The active layer 30 includes a p-type semiconductor and an n-typesemiconductor to form a pn junction, and absorbs external light togenerate excitons and then separates the generated excitons into holesand electrons.

The active layer 30 includes the compound represented by ChemicalFormula 1. The compound may act as a p-type semiconductor compound inthe active layer 30.

The compound is a compound selectively absorbing light in a greenwavelength region, and the active layer 30 including the compound mayhave a maximum absorption wavelength (λ_(max)) in a wavelength region ofgreater than or equal to about 510 nm and less than about 560 nm, forexample about 520 nm to about 555 nm.

The active layer 30 may exhibit a light absorption curve having arelatively narrow full width at half maximum (FWHM) of about 50 nm toabout 110 nm, for example about 50 nm to about 100 nm. Accordingly, theactive layer 30 has high selectivity for light in a green wavelengthregion.

The active layer may have an absorption coefficient of greater than orequal to about 5.5×10⁴ cm⁻¹, for example about 5.8×10⁴ cm⁻¹ to about10×10⁴ cm⁻¹ or about 7.0×10⁴ cm⁻¹ to about 10×10⁴ cm⁻¹ when includingthe compound Chemical Formula 1 and C60 in a volume ratio of about 0.9:1to about 1.1:1, for example about 1:1.

The active layer 30 may further include an n-type semiconductor compoundfor forming a pn junction.

The n-type semiconductor compound may be sub-phthalocyanine or asub-phthalocyanine derivative, fullerene or a fullerene derivative,thiophene or a thiophene derivative, or a combination thereof.

The fullerene may include C60, C70, C76, C78, C80, C82, C84, C90, C96,C240, C540, a mixture thereof, a fullerene nanotube, etc. The fullerenederivative may refer to compounds of these fullerenes having asubstituent attached thereto. The fullerene derivative may include asubstituent such as alkyl group, aryl group, or a heterocyclic group.Examples of the aryl groups and heterocyclic groups may be are a benzenering, a naphthalene ring, an anthracene ring, a phenanthrene ring, afluorene ring, a triphenylene ring, a naphthacene ring, a biphenyl ring,a pyrrole ring, a furan ring, a thiophene ring, an imidazole ring, anoxazole ring, a thiazole ring, a pyridine ring, a pyrazine ring, apyrimidine ring, a pyridazine ring, an indolizine ring, an indole ring,a benzofuran ring, a benzothiophene ring, an isobenzofuran ring, abenzimidazole ring, an imidazopyridine ring, a quinolizidine ring, aquinoline ring, a phthalazine ring, a naphthyridine ring, a quinoxalinering, a quinoxazoline ring, an isoquinoline ring, a carbazole ring, aphenanthridine ring, an acridine ring, a phenanthroline ring, athianthrene ring, a chromene ring, an xanthene ring, a phenoxathin ring,a phenothiazine ring, or a phenazine ring.

The sub-phthalocyanine or the sub-phthalocyanine derivative may berepresented by Chemical Formula 8.

In Chemical Formula 8,

each of R³¹ to R³³ are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C₃ to C₃₀ heteroarylgroup, a halogen, a halogen-containing group, and a combination thereof,

each of a, b, and c are integers ranging from 1 to 3, and

Z is a monovalent substituent.

For example, Z may be a halogen or a halogen-containing group, forexample, F, Cl, a F-containing group, or a Cl-containing group.

The halogen refers to F, Cl, Br, or I and the halogen-containing grouprefers to alkyl group where at least one of hydrogen is replaced by F,Cl, Br, or I.

The thiophene derivative may be, for example represented by ChemicalFormula 9 or 10 but is not limited thereto.

In Chemical Formulae 9 and 10,

each of T¹, T², and T³ are aromatic rings including substituted orunsubstituted thiophene moieties,

each of T¹, T², and T³ are independently present or are fused to eachother,

each of X³ to X⁸ are independently selected from hydrogen, a substitutedor unsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstitutedC₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heterocyclic group, acyano group, or a combination thereof, and

each of EWG¹ and EWG² are independently electron withdrawing groups.

For example, in Chemical Formula 9, at least one of X³ to X⁸ is anelectron withdrawing group, for example a cyano-containing group.

The active layer 30 may further include a second p-type semiconductorcompound selectively absorbing green light. The p-type semiconductorcompound may be a compound represented by Chemical Formula 11.

In Chemical Formula 11,

each of R⁴¹ to R⁴³ are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ aliphatic hydrocarbon group, asubstituted or unsubstituted C₆ to C₃₀ aromatic hydrocarbon group, asubstituted or unsubstituted C₁ to C₃₀ aliphatic heterocyclic group, asubstituted or unsubstituted C2 to C₃₀ aromatic heterocyclic group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryloxy group, thiol group, a substituted orunsubstituted C₆ to C₃₀ alkylthio group, a substituted or unsubstitutedC₆ to C₃₀ arylthio group, a cyano group, a cyano-containing group, ahalogen, a halogen-containing group, a substituted or unsubstitutedsulfonyl group (e.g., a substituted or unsubstituted C₁ to C₃₀aminosulfonyl group, a substituted or unsubstituted C₁ to C₃₀alkylsulfonyl group or a substituted or unsubstituted C₆ to C₃₀arylsulfonyl group), or a combination thereof, or two adjacent groups ofR⁴¹ to R⁴³ are linked with each other to provide a fused ring,

each of L¹ to L³ are independently a single bond, a substituted orunsubstituted C₁ to C₃₀ alkylene group, a substituted or unsubstitutedC₆ to C₃₀ arylene group, a divalent substituted or unsubstituted C₃ toC₃₀ heterocyclic group, or a combination thereof,

each of R⁵¹ to R⁵³ are independently a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C₃ to C₃₀ heterocyclic group, a substitutedor unsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstitutedamine group (e.g., a substituted or unsubstituted C₁ to C₃₀ alkylaminegroup or a substituted or unsubstituted C₆ to C₃₀ arylamine group), asubstituted or unsubstituted silyl group, or a combination thereof, and

each of a to c are independently an integer ranging from 0 to 4.

The second p-type semiconductor compound selectively absorbing greenlight may be included in an amount of about 500 to about 1500 parts byweight based on 100 parts by weight of the compound represented byChemical Formula 1.

The active layer 30 may be a single layer or a multilayer. The activelayer 30 may be, for example, an intrinsic layer (I layer), a p-typelayer/I layer, an I layer/n-type layer, a p-type layer/I layer/n-typelayer, a p-type layer/n-type layer, etc.

The intrinsic layer (I layer) may include the compound of ChemicalFormula 1 and the n-type semiconductor compound in a ratio of about1:100 to about 100:1. The compound of Chemical Formula 1 and the n-typesemiconductor compound may be included in a ratio ranging from about1:50 to about 50:1 within the range, for example, about 1:10 to about10:1, for example, about 1:1. When the compound of Chemical Formula 1and the n-type semiconductor compound have a composition ratio withinthe range, an exciton may be effectively produced, and a pn junction maybe effectively formed.

The p-type layer may include the semiconductor compound of ChemicalFormula 1, and the n-type layer may include the n-type semiconductorcompound.

The active layer 30 may have a thickness of about 1 nm to about 500 nmand specifically, about 5 nm to about 300 nm. When the active layer 30has a thickness within the range, the active layer may effectivelyabsorb light, effectively separate holes from electrons, and deliverthem, thereby effectively improving photoelectric conversion efficiency.An optimal thickness of a thin film may be, for example, determined byan absorption coefficient of the active layer 30, and may be, forexample, a thickness being capable of absorbing light of at least about70% or more, for example about 80% or more, and for another exampleabout 90%.

In the organic photoelectric device 100, when light enters from thefirst electrode 10 and/or second electrode 20, and when the active layer30 absorbs light in a given or predetermined wavelength region, excitonsmay be produced from the inside. The excitons are separated into holesand electrons in the active layer 30, and the separated holes aretransported to an anode that is one of the first electrode 10 and thesecond electrode 20 and the separated electrons are transported to thecathode that is the other of and the first electrode 10 and the secondelectrode 20 so as to flow a current in the organic photoelectricdevice.

Hereinafter, an organic photoelectric device according to anotherexample embodiment is described with reference to FIG. 2.

FIG. 2 is a cross-sectional view showing an organic photoelectric deviceaccording to example embodiments.

Referring to FIG. 2, an organic photoelectric device 200 according toexample embodiments includes a first electrode 10 and a second electrode20 facing each other, and an active layer 30 between the first electrode10 and the second electrode 20, like the above example embodimentillustrated in FIG. 1.

However, the organic photoelectric device 200 according to exampleembodiments further includes charge auxiliary layers 40 and 45 betweenthe first electrode 10 and the active layer 30, and the second electrode20 and the active layer 30, unlike the above example embodimentillustrated in FIG. 1. The charge auxiliary layers 40 and 45 mayfacilitate the transfer of holes and electrons separated from the activelayer 30, so as to increase efficiency.

The charge auxiliary layers 40 and 45 may be at least one selected froma hole injection layer (HIL) for facilitating hole injection, a holetransport layer (HTL) for facilitating hole transport, an electronblocking layer (EBL) for reducing or preventing electron transport, anelectron injection layer (EIL) for facilitating electron injection, anelectron transport layer (ETL) for facilitating electron transport, anda hole blocking layer (HBL) for reducing or preventing hole transport.

The charge auxiliary layers 40 and 45 may include, for example, anorganic material, an inorganic material, or an organic/inorganicmaterial. The organic material may be an organic compound having hole orelectron characteristics, and the inorganic material may be, forexample, a metal oxide such as molybdenum oxide, tungsten oxide, nickeloxide, etc.

The hole transport layer (HTL) may include one selected from, forexample, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS), polyarylamine, poly(N-vinylcarbazole), polyaniline,polypyrrole, N,N,N′,N′-tetrakis(4-methoxyphenyl)-benzidine (TPD),4-bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl (α-NPD), m-MTDATA,4,4′,4″-tris(N-carbazolyl)-triphenylamine (TCTA), and a combinationthereof, but is not limited thereto.

The electron blocking layer (EBL) may include one selected from, forexample, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS), polyarylamine, poly(N-vinylcarbazole), polyaniline,polypyrrole, N,N,N′,N′-tetrakis(4-methoxyphenyl)-benzidine (TPD),4,4′-bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl (α-NPD), m-MTDATA,4,4′,4″-tris(N-carbazolyl)-triphenylamine (TCTA), and a combinationthereof, but is not limited thereto.

The electron transport layer (ETL) may include one selected from, forexample, 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA),bathocuproine (BCP), LiF, Alq₃, Gaq₃, Inq₃, Znq₂, Zn(BTZ)₂, BeBq₂, and acombination thereof, but is not limited thereto.

The hole blocking layer (HBL) may include one selected from, forexample, 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA),bathocuproine (BCP), LiF, Alq₃, Gaq₃, Inq₃, Znq₂, Zn(BTZ)₂, BeBq₂, and acombination thereof, but is not limited thereto.

Either one of the charge auxiliary layers 40 and 45 may be omitted.

The organic photoelectric device may be applied to various fields, forexample a solar cell, an image sensor, a photo-detector, a photo-sensor,and an organic light emitting diode (OLED), but is not limited thereto.

Hereinafter, an example of an image sensor including the organicphotoelectric device is described referring to drawings. As an exampleof an image sensor, an organic CMOS image sensor is described.

FIG. 3 is a schematic top plan view showing an organic CMOS image sensoraccording to example embodiments, and FIG. 4 is a cross-sectional viewshowing the organic CMOS image sensor of FIG. 3.

Referring to FIGS. 3 and 4, an organic CMOS image sensor 300 accordingto example embodiments includes a semiconductor substrate 310 integratedwith photo-sensing devices 50B and 50R, a transmission transistor (notshown), a charge storage 55, a lower insulation layer 60, a color filterlayer 70, an upper insulation layer 80, and an organic photoelectricdevice 100.

The semiconductor substrate 310 may be a silicon substrate, and isintegrated with the photo-sensing device 50, the transmission transistor(not shown), and the charge storage 55. The photo-sensing devices 50Rand 50B may be photodiodes.

The photo-sensing devices 50B and 50R, the transmission transistor (notshown), and/or the charge storage 55 may be integrated in each pixel,and as shown in the drawing, the photo-sensing devices 50B and 50R maybe respectively included in a blue pixel and a red pixel and the chargestorage 55 may be included in a green pixel.

The photo-sensing devices 50B and 50R sense light, the informationsensed by the photo-sensing devices may be transferred by thetransmission transistor, the charge storage 55 is electrically connectedto the organic photoelectric device 100, and the information of thecharge storage 55 may be transferred by the transmission transistor.

In the drawings, the photo-sensing devices 50B and 50R are, for example,arranged in parallel without limitation, and the blue photo-sensingdevice 50B and the red photo-sensing device 50R may be stacked in avertical direction.

A metal wire (not shown) and a pad (not shown) are formed on thesemiconductor substrate 110. In order to decrease signal delay, themetal wire and pad may at least partially comprise a metal havingrelatively low resistivity, for example, aluminum (Al), copper (Cu),silver (Ag), and alloys thereof, but are not limited thereto. In someexample embodiments, the metal wire and pad may be positioned under thephoto-sensing devices 50B and 50R.

The lower insulation layer 60 is formed on the metal wire and the pad.The lower insulation layer 60 may at least partially comprise aninorganic insulating material including a silicon oxide and/or a siliconnitride, or a low dielectric constant (low K) material including SiC,SiCOH, SiCO, and SiOF. The lower insulation layer 60 has a trenchexposing the charge storage 55. The trench may be filled with fillers.

A color filter layer 70 is formed on the lower insulation layer 60. Thecolor filter layer 70 includes a blue filter 70B formed in the bluepixel and selectively transmitting blue light and a red filter 70Rformed in the red pixel and selectively transmitting red light. Inexample embodiments, a green filter is not included, but a green filtermay be further included.

The color filter layer 70 may be omitted. For example, when the bluephoto-sensing device 50B and the red photo-sensing device 50R arestacked in a vertical direction, the blue photo-sensing device 50B andthe red photo-sensing device 50R may selectively absorb light in eachwavelength region depending on their stack depth, and the color filterlayer 70 may not be equipped.

The upper insulation layer 80 is formed on the color filter layer 70.The upper insulation layer 80 may eliminate a step caused by the colorfilter layer 70 and smoothes the surface. The upper insulation layer 80and the lower insulation layer 60 may include a contact hole (not shown)exposing a pad, and a through-hole 85 exposing the charge storage 55 ofthe green pixel.

The organic photoelectric device 100 is formed on the upper insulationlayer 80. The organic photoelectric device 100 includes the firstelectrode 10, the active layer 30, and the second electrode 20 asdescribed above.

The first electrode 10 and the second electrode 20 may be transparentelectrodes, and the active layer 30 is the same as described above. Theactive layer 30 may selectively absorb and/or sense light in a greenwavelength region and may replace a color filter of a green pixel.

When light enters from the second electrode 20, the light in a greenwavelength region may be mainly absorbed in the active layer 30 andphotoelectrically converted, while the light in the rest of thewavelength regions passes through first electrode 10 and may be sensedin the photo-sensing devices 50B and 50R.

As described above, the organic photoelectric devices selectivelyabsorbing light in a green wavelength region are stacked and thereby asize of an image sensor may be decreased and a down-sized image sensormay be realized.

As described above, the compound represented by the Chemical Formula 1may be used as a semiconductor compound, aggregation between compoundsin a thin film state is inhibited, and thereby light absorptioncharacteristics depending on a wavelength may be maintained. Thereby,green wavelength selectivity may be maintained, crosstalk caused byunnecessary absorption of other light except a green wavelength regionmay be decreased and sensitivity may be increased.

In FIG. 4, the organic photoelectric device 100 of FIG. 1 is included,but it is not limited thereto, and thus the organic photoelectric device200 of FIG. 2 may be applied in the same manner. FIG. 5 shows astructure of an image sensor having such a structure, and is across-sectional view of an organic CMOS image sensor 400 including theorganic photoelectric device 200 in FIG. 2.

FIG. 6 is a cross-sectional view showing the organic CMOS image sensoraccording to example embodiments.

Referring to FIG. 6, the organic CMOS image sensor 500 includes asemiconductor substrate 310 integrated with photo-sensing devices 50Band 50R, a transmission transistor (not shown), a charge storage 55, aninsulation layer 80, and an organic photoelectric device 100, like theexample embodiment illustrated in FIG. 5.

However, the organic CMOS image sensor 500 according to the exampleembodiment illustrated in FIG. 6 includes the blue photo-sensing device50B and the red photo-sensing device 50R that are stacked and does notinclude a color filter layer 70, unlike the example embodimentillustrated in FIG. 5. The blue photo-sensing device 50B and the redphoto-sensing device 50R are electrically connected to the chargestorage 55, and the information of the charge storage 55 may betransferred by the transmission transistor (not shown). The bluephoto-sensing device 50B and the red photo-sensing device 50R mayselectively absorb light in each wavelength region depending on a stackdepth.

As described above, the organic photoelectric devices selectivelyabsorbing light in a green wavelength region are stacked and the redphoto-sensing device and the blue photo-sensing device are stacked, andthereby a size of an image sensor may be decreased and a down-sizedimage sensor may be realized. As described above, the organicphotoelectric device 100 has improved green wavelength selectivity, andcrosstalk caused by unnecessary absorption light in a wavelength regionexcept green may be decreased while increasing sensitivity.

In FIG. 6, the organic photoelectric device 100 of FIG. 1 is included,but it is not limited thereto, and thus the organic photoelectric device200 of FIG. 2 may be applied in the same manner.

FIG. 7 is a schematic view showing an organic CMOS image sensoraccording to example embodiments.

Referring to FIG. 7, the organic CMOS image sensor according to exampleembodiments includes a green photoelectric device (G) selectivelyabsorbing light in a green wavelength region, a blue photoelectricdevice (B) selectively absorbing light in a blue wavelength region, anda red photoelectric device selectively absorbing light in a redwavelength region that are stacked.

In the drawing, the red photoelectric device, the green photoelectricdevice, and the blue photoelectric device are sequentially stacked, butthe stack order may be changed without limitation.

The green photoelectric device may be the above organic photoelectricdevice 100, the blue photoelectric device may include electrodes facingeach other and an active layer interposed therebetween and including anorganic material selectively absorbing light in a blue wavelengthregion, and the red photoelectric device may include electrodes facingeach other and an active layer interposed therebetween and including anorganic material selectively absorbing light in a red wavelength region.

As described above, the organic photoelectric device selectivelyabsorbing light in a green wavelength region, the organic photoelectricdevice selectively absorbing light in a red wavelength region, and theorganic photoelectric device selectively absorbing light in a bluewavelength region are stacked, and thereby a size of an image sensor maybe decreased and a down-sized image sensor may be realized.

The image sensor may have a color difference (ΔE*ab) of less than about4.0, for example less than or equal to about 3.9, less than or equal toabout 3.2, and less than or equal to about 1.6. The ΔE*ab is defined asa distance between two points on a L*a*b* color space by CIE (CommissionInternational de L' Eclairage) in 1976. For example, the colordifference may be calculated according to Equation 1.ΔE=√{square root over ((ΔL*)²+(Δa*)²+(Δb*)²)}  [Equation 1]

In the Equation 1,

ΔL* denotes a change of a color coordinate L* compared with the colorcoordinate Cat room temperature (about 20° C. to about 25° C.),

Δa* denotes a change of a color coordinate a* compared with the colorcoordinate a*at room temperature, and

Δb* denotes a change of a color coordinate b* compared with the colorcoordinate b*at room temperature.

The image sensor may realize high sensitivity (YSNR10) of less than orequal to about 100 lux at a color difference (ΔE*ab) of about 3.0.

The image sensor may be applied to various electronic devices, forexample, a mobile phone, a digital camera, and the like but is notlimited thereto.

Hereinafter, the present disclosure is illustrated in more detail withreference to examples. However, these are examples, and the presentdisclosure is not limited thereto.

Synthesis Example 1: Synthesis of Compound Represented by ChemicalFormula 1-1

Compound (1) is synthesized in a method describe in a non-patentreference (Heterocycles 1996, 43, 1927-1935).

3.6 g (14.2 mmmol) of Compound (1), 2.8 g (12.8 mmmol) of 2-(naphthylamino)pyridine, 10 mol % of Pd(dba)₂ (bis(dibenzylideneacetone)palladium(0)), 10 mol % of P(^(t)Bu)₃ (tri-tert-butylphosphine), and 1.5 g ofNaO^(t)Bu (sodium-t-butoxide) are heated and refluxed in 100 ml ofanhydrous toluene for 5 hours. The resultant is cooled down to roomtemperature of 24° C. and concentrated, and a crude product obtainedtherefrom is purified through silica gel column chromatography to obtain2.7 g of Compound (2) (a yield of 65%).

2.0 g (5.7 mmol) of Compound (2) is dissolved in 30 ml of anhydroustetrahydrofuran (THF), the solution is cooled down to 0° C., and 3.9 mlof an n-BuLi solution (1.6 M of a concentration) is added thereto in adropwise fashion within a range of 5° C. After the addition, the mixtureis heated up to 40° C. and then, stirred for 30 minutes. Subsequently,the resultant is cooled down to −78° C., and 1.0 ml of anhydrous DMF isadded thereto. The mixture is added to room temperature of 24° C., anammonium chloride aqueous solution is added thereto, and the mixture isquenched and then, treated with ethyl acetate for an extraction. Anorganic layer therefrom is evaporated and removed to obtain a crudeproduct. The crude product is purified through silica gel chromatographyto obtain 1.0 g of Compound (3) (a yield of 47%).

0.5 g (1.3 mmol) of Compound (3) is suspended in 10 ml of ethanol, 0.3 gof 1H-cyclopenta[b]naphthalene-1,3(2H)-dione is added thereto, and themixture is heated at 50° C. for 2 hours. The resultant is cooled down toroom temperature (24° C.) and then, suction-filtered and dried to obtain0.67 g of a crude product (a yield of 92%). The crude product issublimation-purified to obtain 0.54 g of Compound (4) represented byChemical Formula 1-1 (a yield of 74%, purity of 99%).

¹H NMR (300 MHz, DMSO-d₆): δ 8.8 (d, 1H), 8.5 (s, 1H), 8.4 (s, 1H),8.2-8.3 (m, 4H), 8.2 (d, 1H), 8.1 (s, 1H), 7.9-7.6 (m, 6H), 7.5 (t, 1H),7.4 (d, 1H), 7.3 (dd, 1H), 6.3 (d, 1H), 6.0 (d, 1H), 5.7 (s, 1H).

Synthesis Example 2: Synthesis of Compound Represented by ChemicalFormula 1-2

A compound represented by Chemical Formula 1-2 is synthesized accordingto the same method as Synthesis Example 1 except for using2-(phenylamino)pyrimidine instead of the 2-(naphthyl amino)pyridine (ayield of 74%, purity of 99%).

¹H NMR (300 MHz, CDCl₃): δ 8.7 (s, 2H), 8.4 (d, 2H), 8.0-8.2 (m, 5H),7.4-7.9 (m, 8H), 7.2 (dd, 1H), 6.1 (d, 1H).

Synthesis Example 3: Synthesis of Compound Represented by ChemicalFormula 1-3

A compound represented by Chemical Formula 1-3 is synthesized accordingto the same method as Synthesis Example 1 except for using2-(phenylamino)pyridine instead of the 2-(naphthyl amino)pyridine (ayield of 74%, purity of 99%).

¹H NMR (300 MHz, DMSO-d₆): δ 8.8 (d, 1H), 8.5 (s, 1H), 8.4 (s, 1H), 8.3(m, 3H), 8.1 (s, 1H), 7.6-7.8 (m, 6H), 7.6 (d, 2H), 7.3 (dd, 1H), 6.5(d, 1H), 6.1 (d, 1H).

Synthesis Example 4: Synthesis of Compound Represented by ChemicalFormula 1-4

A compound represented by Chemical Formula 1-4 is synthesized accordingto the same method as Synthesis Example 1 except for using1,3-dimethyl-2-thioxohexahydropyrimidine-4,6-dione instead of the1H-cyclopenta[b]naphthalene-1,3(2H)-dione (a yield of 74%, purity of99%).

¹H NMR (300 MHz, CDCl₃): δ 8.8 (d, 1H), 8.7 (s, 1H), 8.2 (d, 1H), 8.0(d, 2H), 7.9 (d, 2H), 7.8 (t, 1H), 7.6 (m, 2H), 7.5 (m, 3H), 7.1 (t,1H), 6.3 (d, 1H), 6.2 (d, 1H), 3.9 (d, 6H).

Synthesis Example 5: Synthesis of Compound Represented by ChemicalFormula 1-5

A compound represented by Chemical Formula 1-5 is synthesized accordingto the same method as Synthesis Example 1 except for using2-(phenylamino)pyridine instead of the 2-(naphthylamino)pyridine and1,3-dimethyl-2-thioxohexahydropyrimidine-4,6-dione instead of the1H-cyclopenta[b]naphthalene-1,3(2H)-dione (a yield of 74%, purity of99%).

¹H NMR (300 MHz, CDCl₃): δ 8.8 (d, 1H), 8.7 (s, 1H), 8.0 (d, 1H), 7.7(m, 4H), 7.4 (d, 2H), 7.1 (t, 1H), 6.5 (d, 1H), 6.3 (d, 1H), 3.9 (d,6H).

Comparative Synthesis Example 1: Synthesis of Compound Represented byChemical Formula 1-6

A compound represented by Chemical Formula 1-6 is synthesized accordingto the same method as Synthesis Example 1 except for using2-iodothiophene instead of the compound 1 and N-(2-naphthyl)anilineinstead of the 2-(naphthylamino)pyridine (a yield of 74%, purity of99%).

¹H NMR (300 MHz, DMSO-d₆): δ 8.5 (s, 1H), 8.4 (s, 1H), 8.2-8.3 (m, 4H),8.2 (d, 1H), 8.1 (s, 1H), 7.9-7.6 (m, 7H), 7.5 (t, 1H), 7.4 (d, 1H), 7.3(dd, 1H), 6.3 (d, 1H), 6.0 (d, 1H), 5.7 (s, 1H).

Reference Synthesis Example 1: Synthesis of Compound Represented byChemical Formula 1-7

A compound represented by Chemical Formula 1-7 is synthesized accordingto the same method as Synthesis Example 1 except for usingN-(2-naphthyl)aniline instead of the 2-(naphthyl amino)pyridine (a yieldof 74%, purity of 99%).

¹H NMR (300 MHz, DMSO-d₆): δ 8.8 (s, 1H), 8.7 (d, 1H), 8.5 (s, 1H), 8.4(s, 1H), 8.2-8.3 (m, 4H), 8.2 (d, 1H), 8.1 (s, 1H), 7.9-7.6 (m, 5H), 7.5(t, 1H), 7.4 (d, 1H), 7.3 (dd, 1H), 6.3 (d, 1H), 6.0 (d, 1H), 5.7 (s,1H).

Reference Synthesis Example 2: Synthesis of Compound Represented byChemical Formula 1-8

A compound represented by Chemical Formula 1-7 is synthesized accordingto the same method as Synthesis Example 1 except for using4-(naphthylamino)pyridine instead of the 2-(naphthyl amino)pyridine (ayield of 74%, purity of 99%).

¹H NMR (300 MHz, DMSO-d₆): δ 8.8 (d, 2H), 8.5 (s, 1H), 8.4 (s, 1H),8.2-8.3 (m, 4H), 8.2 (d, 1H), 8.1 (s, 1H), 7.9-7.6 (m, 5H), 7.5 (t, 1H),7.4 (d, 1H), 7.3 (dd, 1H), 6.3 (d, 1H), 6.0 (d, 1H), 5.7 (s, 1H).

Light Absorption Characteristics of Compound of Synthesis Examples 1 to5, Comparative Synthesis Example 1, and Reference Synthesis Examples 1and 2

Light absorption characteristics (absorption wavelength, absorptionintensity, and a full width at half maximum (FWHM)) of the compounds ofSynthesis Examples 1 to 5, Comparative Synthesis Example 1, andReference Synthesis Examples 1 and 2 depending on a wavelength areevaluated. The light absorption characteristics are evaluated in asolution state and a thin film state.

The light absorption characteristics in the solution state are evaluatedby dissolving 5 mg of each compound of Synthesis Examples 1 to 5,Comparative Synthesis Example 1, and Reference Synthesis Examples 1 and2 in 250 ml of toluene and ten times diluting each solution.

The light absorption characteristics in the thin film state areevaluated by thermally depositing each compound of Synthesis Examples 1to 5, Comparative Synthesis Example 1, and Reference Synthesis Examples1 and 2 and C60 in a volume ratio of 1:1 under a high vacuum (<10⁻⁷Torr) at a speed of 0.5 to 1.0 Å/s to respectively form a 70 nm-thickthin film and radiating an ultraviolet (UV)-visible ray (UV-Vis) theretowith Cary 5000 UV spectroscopy (Varian Medical System, Inc.). The lightabsorption characteristics results of the compounds of SynthesisExamples 1 to 5, Comparative Synthesis Example 1, and ReferenceSynthesis Examples 1 and 2 are shown in Table 1.

TABLE 1 Solution Thin film absorption absorption λ_(max) coefficientFWHM λ_(max) coefficient FWHM (nm) (10⁵ cm⁻¹) (nm) (nm) (10⁴ cm⁻¹) (nm)Synthesis 533 1.2 40 552 7.8 105 Example 1 Synthesis 526 1.2 34 540 7.9100 Example 2 Synthesis 537 1.1 32 554 8.2 108 Example 3 Synthesis 5151.2 27 530 7.4 97 Example 4 Synthesis 515 1.2 28 520 9.1 95 Example 5Comparative 540 1.0 51 560 5.3 110 Synthesis Example 1 Reference 540 0.952 560 5.3 111 Synthesis Example 1 Reference 541 0.9 52 560 5.3 111Synthesis Example 2

Referring to Table 1, the compounds of Synthesis Examples 1 to 5 exhibita maximum absorption wavelength in a green wavelength region (e.g., 520nm to 554 nm in a thin film state), a narrow full width at half maximum(FWHM), and a high absorption coefficient compared with the compounds ofComparative Synthesis Example 1 and Reference Synthesis Examples 1 and2. Accordingly, the compounds of Synthesis Examples 1 to 5 exhibitexcellent green wavelength selectivity and absorption intensity comparedwith the compounds of Comparative Synthesis Example 1 and ReferenceSynthesis Examples 1 and 2.

Example 1: Manufacture of Organic Photoelectric Device

Indium tin oxide (ITO) is sputtered on a glass substrate to form anabout 150 nm-thick anode, and a 150 nm-thick active layer is formedthereon by codepositing the compound represented by Chemical Formula 1-1according to Synthesis Example 1 (a p-type semiconductor compound) andC60 (an n-type semiconductor compound) in a thickness ratio of 1:1. Onthe active layer, a 10 nm-thick molybdenum oxide (MoOx, 0<x≤3) thin filmis formed as a charge auxiliary layer. Subsequently, on the molybdenumoxide thin film, ITO is sputtered to form a 7 nm-thick cathode and thusmanufacture an organic photoelectric device.

Examples 2 to 5: Manufacture of Organic Photoelectric Device

Each organic photoelectric device of Examples 2 to 5 is manufacturedaccording to the same method as Example 1 except for respectively usingthe compounds of Synthesis Examples 2 to 5 instead of the compound ofSynthesis Example 1.

Comparative Example 1: Manufacture of Organic Photoelectric Device

An organic photoelectric device of Comparative Example 1 is manufacturedaccording to the same method as Example 1 except for using the compoundof Comparative Synthesis Example 1 instead of the compound of SynthesisExample 1.

External Quantum Efficiency (EQE) of Organic Photoelectric Device

External quantum efficiency (EQE) of the organic photoelectric devicesof Example 1 to 5 and Comparative Example 1 depending on a wavelengthand a voltage is evaluated.

The external quantum efficiency is measured by using an IPCE measurementsystem (McScience Inc., Korea). First, the IPCE measurement system iscalibrated by using a Si photodiode (Hamamatsu Photonics K.K., Japan)and then, respectively equipped on the organic photoelectric devices ofExamples 1 to 5 and Comparative Example 1, and their external quantumefficiency at a wavelength ranging from about 350 to about 750 nm ismeasured. The results are shown in Table 2.

Color Reproducibility (ΔE*ab) and Sensitivity (YSNR10) of Image Sensor

An image sensor is manufactured by respectively disposing the organicphotoelectric devices of Examples 1 to 5 and Comparative Example 1 in aposition of the organic photoelectric device 100 of the image sensor 300shown in FIG. 4.

A minimum color difference ΔE*ab (a color difference between a reflectedcolor and a transmitted color) of 24 colors of a Macbeth chart when a18% gray patch of the Macbeth chart is taken a photograph of under D-65of a standard light source. The color difference ΔE*ab is calculatedaccording to Equation 1.

$\begin{matrix}{{\Delta\; E} = \sqrt{\left( {\Delta\; L^{*}} \right)^{2} + \left( {\Delta\; a^{*}} \right)^{2} + \left( {\Delta\; b^{*}} \right)^{2}}} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

In Equation 1,

ΔL* denotes a change of a color coordinate L* from the color coordinateL* at 23° C.,

Δa* denotes a change of a color coordinate a* from the color coordinatea* at 23° C., and

Δb* denotes a change of a color coordinate b* from the color coordinateb* at 23° C.

Herein, lens having a F value of 2.8 and transmittance of 80% are used,and general interference-type lens are used as an infrared ray-cuttingfilter. The image sensor is set to have a pixel size of 1.4 μm and aframe rate of 15 fps.

TABLE 2 Organic photoelectric device EQE (%) (at −3 V) Min. ΔE*abExample 1 68 3.5 Example 2 62 2.5 Example 3 76 3.9 Example 4 74 3.0Example 5 74 3.0 Comparative Example 1 60 4.0

As shown in Table 2, the organic photoelectric devices of Examples 1 to5 exhibit excellent external quantum efficiency compared with theorganic photoelectric device of Comparative Example 1. In addition, theorganic photoelectric devices of Examples 1 to 5 exhibit a low minimumcolor difference ΔE*ab of less than or equal to 3.9 compared with theorganic photoelectric devices of Comparative Example 1.

Sensitivity (YSNR10) of Image Sensor

YSNR10 of the image sensors of Examples 1, 2, 4, and 5 at ΔE*ab=3.5 ismeasured in a method described in Juha Alakarhu's “Image Sensors andImage Quality in Mobile Phones” in an outline collection of 2007International Image Sensor Workshop (Ogunquit Me., USA).

The YSNR10 is obtained when a 18% gray patch of the Macbeth chart istaken a photograph of under a standard light source of D-65.

Herein, lens having a F value of 2.8 and transmittance of 80% is used,and interference-type lens are used as an infrared ray-cutting filter.The image sensors are set to have a pixel size of 1.4 μm and a framerate of 15 fps.

The obtained colors are calibrated by using CCM (Color CorrectionMatrix), and the results are shown in Table 3.

TABLE 3 Organic photoelectric device YSNR10 (lux) (ΔE*ab = 3.5) Example1 80.7 Example 2 85.6 Example 4 78.1 Example 5 77.8

Referring to Table 3, the image sensors respectively including theorganic photoelectric devices of Examples 1, 2, 4, and 5 exhibit YSNR10of less than or equal to 85.6 lux at ΔE*ab=3.5. Accordingly, the imagesensors may have high sensitivity at a considerably high image qualitypixel of 1.4 μm.

On the other hand, an image sensor including the organic photoelectricdevice of Comparative Example 1 may not have ΔE*ab=3.5, and thus itsYSNR10 is impossible to calculate.

While this disclosure has been described in connection with what ispresently considered to be practical example embodiments, it is to beunderstood that the inventive concepts are not limited to the disclosedembodiments, but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

What is claimed is:
 1. A compound represented by Chemical Formula 1:

wherein, in Chemical Formula 1, Ar is selected from a substituted orunsubstituted 5-membered aromatic ring, a substituted or unsubstituted6-membered aromatic ring, and a condensed ring of two or more of theforegoing rings, X¹ is Se, each of R¹ to R³ are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, and each of Ar¹ and Ar² areindependently selected from a substituted or unsubstituted C₆ to C₃₀aryl group, and a substituted or unsubstituted C₃ to C₃₀ heteroarylgroup, provided that at least one of Ar¹ and Ar² is a heteroaryl groupincluding at least one nitrogen (N) at an ortho position with respect toa bond with the nitrogen (N) of Chemical Formula
 1. 2. The compound ofclaim 1, wherein, in Chemical Formula 1, at least one of Ar¹ and Ar² isselected from a substituted or unsubstituted pyrrolyl group, asubstituted or unsubstituted prazolyl group, a substituted orunsubstituted midazolyl group, a substituted or unsubstituted oxazolylgroup, a substituted or unsubstituted isoxazolyl group, a substituted orunsubstituted thiazolyl group, a substituted or unsubstitutedisothiazolyl group, a substituted or unsubstituted pyridinyl group, asubstituted or unsubstituted pyridazinyl group, a substituted orunsubstituted pyrimidinyl group, a substituted or unsubstitutedpyrazinyl group, a substituted or unsubstituted indolyl group, asubstituted or unsubstituted quinolinyl group, a substituted orunsubstituted isoquinolinyl group, a substituted or unsubstitutednaphthyridinyl group, a substituted or unsubstituted cinnolinyl group, asubstituted or unsubstituted quinazolinyl group, a substituted orunsubstituted phthalazinyl group, a substituted or unsubstitutedbenzotriazinyl group, a substituted or unsubstituted pyridopyrazinylgroup, a substituted or unsubstituted pyridopyrimidinyl group, asubstituted or unsubstituted pyridopyridazinyl group, a substituted orunsubstituted thienyl group, a substituted or unsubstituted benzothienylgroup, a substituted or unsubstituted selenophenyl group, and asubstituted or unsubstituted benzoselenophenyl group, and the functionalgroups may include at least one nitrogen (N) at an ortho position withrespect to a bond with the nitrogen (N).
 3. The compound of claim 1,wherein the compound represented by Chemical Formula 1 is represented byChemical Formula 2:

wherein, in Chemical Formula 2, Ar is selected from a substituted orunsubstituted 5-membered aromatic ring, a substituted or unsubstituted6-membered aromatic ring, and a condensed ring of two or more of theforegoing rings, X¹ is Se, each of R¹ to R³ are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, each of R^(4a) to R^(4e) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C₃ to C₃₀ heteroaryl group, a halogen, acyano group (—CN), a cyano-containing group, and a combination thereof,or optionally two adjacent groups of R^(4a) to R^(4e) are linked witheach other to provide a 5-membered aromatic ring or a 6-memberedaromatic ring, a is an integer of 0 or 1, X² is nitrogen (N), and Ar′¹is heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).
 4. The compoundof claim 3, wherein, in Chemical Formula 2, Ar′¹ is selected from asubstituted or unsubstituted pyrrolyl group, a substituted orunsubstituted pyrazolyl group, a substituted or unsubstituted imidazolylgroup, a substituted or unsubstituted oxazolyl group, a substituted orunsubstituted isoxazolyl group, a substituted or unsubstituted thiazolylgroup, a substituted or unsubstituted isothiazolyl group, a substitutedor unsubstituted pyridinyl group, a substituted or unsubstitutedpyridazinyl group, a substituted or unsubstituted pyrimidinyl group, asubstituted or unsubstituted pyrazinyl group, a substituted orunsubstituted indolyl group, a substituted or unsubstituted quinolinylgroup, a substituted or unsubstituted isoquinolinyl group, a substitutedor unsubstituted naphthyridinyl group, a substituted or unsubstitutedcinnolinyl group, a substituted or unsubstituted quinazolinyl group, asubstituted or unsubstituted phthalazinyl group, a substituted orunsubstituted benzotriazinyl group, a substituted or unsubstitutedpyridopyrazinyl group, a substituted or unsubstituted pyridopyrimidinylgroup, a substituted or unsubstituted pyridopyridazinyl group, asubstituted or unsubstituted thienyl group, a substituted orunsubstituted benzothienyl group, a substituted or unsubstitutedselenophenyl group, and a substituted or unsubstituted benzoselenophenylgroup.
 5. The compound of claim 1, wherein the compound represented byChemical Formula 1 is represented by one of Chemical Formulae 3-1 to3-6:

wherein, in Chemical Formulae 3-1 to 3-6, Ar is selected from asubstituted or unsubstituted 5-membered aromatic ring, a substituted orunsubstituted 6-membered aromatic ring, and a condensed ring of two ormore of the foregoing rings, X¹ is Se, each of R¹ to R³ areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C₃ to C₃₀ heteroaryl group, a halogen, acyano group (—CN), a cyano-containing group, and a combination thereof,each of R^(4a) to R^(4e) or R^(5a) to R^(5d) are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring and optionally two adjacentgroups of R^(5a) to R^(5d) are linked with each other to provide a5-membered aromatic ring or a 6-membered aromatic ring, and each of aand b are independently an integer of 0 or
 1. 6. The compound of claim1, wherein a ring group represented by Ar and bound to a methine groupis represented by Chemical Formula 4:

wherein, in Chemical Formula 4, Ar′ is selected from a substituted orunsubstituted 5-membered aromatic ring, a substituted or unsubstituted6-membered aromatic ring, and a condensed ring of two or more of theforegoing rings, and Z¹ is O or CR^(b)R^(c), wherein R^(b) and R^(c) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₁₀ alkyl group, a cyano group, or a cyano-containing group, providedthat at least one of R^(b) and R^(c) is a cyano group or acyano-containing group.
 7. The compound of claim 1, wherein the ringgroup represented by Ar and bound to a methine group is a ring grouprepresented by one of Chemical Formulae 5-1 to 5-4:

wherein, in Chemical Formula 5-1, Z¹ is O or CR^(b)R^(c), wherein eachof R^(b) and R^(c) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₁₀ alkyl group, a cyano group, or acyano-containing group, provided that at least one of R^(b) and R^(c) isa cyano group or a cyano-containing group, Y¹ is selected from N andCR^(d), wherein R^(d) is selected from hydrogen and a substituted orunsubstituted C₁ to C₁₀ alkyl group, each of R¹¹, R¹², R¹³, R¹⁴, and R¹⁵are independently selected from hydrogen, a substituted or unsubstitutedC₁ to C₃₀ alkyl group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C4 to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, or R¹² and R¹³ are independently linked with eachother and R¹⁴ and R¹⁵ are independently linked with each other toprovide an aromatic ring, m1 is 0 or 1, and n is 0 or 1,

wherein, in Chemical Formula 5-2, Y² is selected from O, S, Se, Te, andC(R^(e))(CN) wherein R^(e) is selected from hydrogen, a cyano group(—CN), and a C₁ to C₁₀ alkyl group, and each of R¹⁶ and R¹⁷ areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C4 to C₃₀ heteroaryl group, a halogen, acyano group (—CN), and a combination thereof,

wherein, in Chemical Formula 5-3, each of R¹⁸ to R²⁰ are independentlyselected from hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkylgroup, a substituted or unsubstituted C₁ to C₃₀ alkoxy group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C4 to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof,

wherein, in Chemical Formula 5-4, Y² is selected from O, S, Se, Te, andC(R^(e))(CN) wherein R^(e) is selected from hydrogen, a cyano group(—CN), and a C₁ to C₁₀ alkyl group, Y³ is selected from O, S, Se, andTe, Y⁴ is N or NR^(f), Y⁵ is selected from CR^(g), C═O, C═S,C═(CR^(h))(CN), and Chemical Formula 5-4, at least one of Y² and Y⁵ isC═O, each of R^(f), R^(g), and R^(h) are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C4 toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, and optionally Y⁴ and Y⁵ are linkedwith each other to provide a fused ring with a Y⁴-Y⁵-containingpentagonal ring of Chemical Formula 5-4.
 8. The compound of claim 1,wherein the compound is represented by one of Chemical Formulae 6-1 to6-4:

wherein, in Chemical Formula 6-1, X¹ is Se, each of R¹ to R³ areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C₃ to C₃₀ heteroaryl group, a halogen, acyano group (—CN), a cyano-containing group, and a combination thereof,Z¹ is O or CR^(b)R^(c), wherein each of R^(b) and R^(c) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₁₀ alkyl group, a cyano group, or a cyano-containing group, providedthat at least one of R^(b) and R^(c) is a cyano group or acyano-containing group, Y¹ is selected from N and CR^(d), wherein R^(d)is selected from hydrogen and a substituted or unsubstituted C₁ to C₁₀alkyl group, each of R¹¹, R¹², R¹³, R¹⁴, and R¹⁵ are independentlyselected from hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkylgroup, a substituted or unsubstituted C₁ to C₃₀ alkoxy group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C4 to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof or R¹² andR¹³ are independently linked with each other to provide an aromatic ringand R¹⁴ and R¹⁵ are independently linked with each other to provide anaromatic ring, m1 is 0 or 1, n is 0 or 1, each of R^(4a) to R^(4e) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₆ to C₃₀ aryl group,a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, a halogen, acyano group (—CN), a cyano-containing group, and a combination thereof,or optionally two adjacent groups of R^(4a) to R^(4e) are linked witheach other to provide a 5-membered aromatic ring or a 6-memberedaromatic ring, a is an integer of 0 or 1, X² is nitrogen (N), and Ar′¹is a heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N),

wherein, in Chemical Formula 6-2, X¹ is Se, Y² is selected from O, S,Se, Te, and C(R^(e))(CN) wherein R^(e) is selected from hydrogen, acyano group (—CN), and a C₁ to C₁₀ alkyl group, each of R¹, R², R³, R¹⁶,and R¹⁷ are independently selected from hydrogen, a substituted orunsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstituted C₁to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C4 to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, each of R^(4a) to R^(4e) are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C₃ to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof, oroptionally two adjacent groups of R^(4a) to R^(4e) are linked with eachother to provide a 5-membered aromatic ring or a 6-membered aromaticring, a is an integer of 0 or 1, X² is nitrogen (N), and Ar′¹ is aheteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N),

wherein, in Chemical Formula 6-3, X¹ is Se, each of R¹, R², R³, R¹⁸,R¹⁹, and R²⁰ are independently selected from hydrogen, a substituted orunsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstituted C₁to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C4 to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, R^(4a) to R^(4e) are independently selected fromhydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C₃ to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof, oroptionally two adjacent groups of R^(4a) to R^(4e) are linked with eachother to provide a 5-membered aromatic ring or a 6-membered aromaticring, a is an integer of 0 or 1, X² is nitrogen (N), and Ar′¹ is aheteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N),

wherein, in Chemical Formula 6-4, X¹ is Se, Y² is selected from O, S,Se, Te, and C(R^(e))(CN) wherein R^(e) is selected from hydrogen, acyano group (—CN), and a C₁ to C₁₀ alkyl group, Y³ is selected from O,S, Se, and Te, Y⁴ is N or NR^(f), Y⁵ is selected from CR^(g), C═O, C═S,C═(CR^(h))(CN), and Chemical Formula 5-4, at least one of Y² and Y⁵ isC═O, each of R¹, R², R³, R^(f), R^(g), and R^(h) are independentlyselected from hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkylgroup, a substituted or unsubstituted C₁ to C₃₀ alkoxy group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C4 to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof, optionallyY⁴ and Y⁵ are linked with each other to provide a fused ring with aY⁴-Y⁵-containing pentagonal ring of Chemical Formula 5-4, each of R^(4a)to R^(4e) are independently selected from hydrogen, a substituted orunsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C₃ to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, or optionally two adjacent groups of R^(4a) toR^(4e) are linked with each other to provide a 5-membered aromatic ringor a 6-membered aromatic ring, a is an integer of 0 or 1, X² is nitrogen(N), and Ar′¹ is a heteroaryl group including at least one nitrogen (N)at an ortho position with respect to a bond with nitrogen (N).
 9. Thecompound of claim 1, wherein the compound has a maximum absorptionwavelength (λ_(max)) in a wavelength region of greater than or equal toabout 510 nm and less than about 560 nm.
 10. The compound of claim 1,wherein the compound has a maximum absorption wavelength (λ_(max)) in awavelength region of about 520 nm to about 555 nm in a thin film state.11. The compound of claim 1, wherein the compound exhibits a lightabsorption curve having a full width at half maximum (FWHM) of about 50nm to about 110 nm, in a thin film state.
 12. An organic photoelectricdevice, comprising: a first electrode and a second electrode facing eachother, and an active layer between the first electrode and the secondelectrode, the active layer including a compound represented by ChemicalFormula 1:

wherein, in Chemical Formula 1, Ar is selected from a substituted orunsubstituted 5-membered aromatic ring, a substituted or unsubstituted6-membered aromatic ring, and a condensed ring of two or more of theforegoing rings, X¹ is Se, each of R¹ to R³ are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, and each of Ar¹ and Ar² areindependently selected from a substituted or unsubstituted C₆ to C₃₀aryl group, and a substituted or unsubstituted C₃ to C₃₀ heteroarylgroup, provided that at least one of Ar¹ and Ar² is a heteroaryl groupincluding at least one nitrogen (N) at an ortho position with respect toa linking group with the nitrogen (N).
 13. The organic photoelectricdevice of claim 12, wherein, in Chemical Formula 1, at least one of Ar¹and Ar² is selected from a substituted or unsubstituted pyrrolyl group,a substituted or unsubstituted prazolyl group, a substituted orunsubstituted midazolyl group, a substituted or unsubstituted oxazolylgroup, a substituted or unsubstituted isoxazolyl group, a substituted orunsubstituted thiazolyl group, a substituted or unsubstitutedisothiazolyl group, a substituted or unsubstituted pyridinyl group, asubstituted or unsubstituted pyridazinyl group, a substituted orunsubstituted pyrimidinyl group, a substituted or unsubstitutedpyrazinyl group, a substituted or unsubstituted indolyl group, asubstituted or unsubstituted a substituted or unsubstituted quinolinylgroup, a substituted or unsubstituted isoquinolinyl group, a substitutedor unsubstituted naphthyridinyl group, a substituted or unsubstitutedcinnolinyl group, a substituted or unsubstituted quinazolinyl group, asubstituted or unsubstituted phthalazinyl group, a substituted orunsubstituted benzotriazinyl group, a substituted or unsubstitutedpyridopyrazinyl group, a substituted or unsubstituted pyridopyrimidinylgroup, a substituted or unsubstituted pyridopyridazinyl group, asubstituted or unsubstituted thienyl group, a substituted orunsubstituted benzothienyl group, a substituted or unsubstitutedselenophenyl group, and a substituted or unsubstituted benzoselenophenylgroup, and the functional groups may include at least one nitrogen (N)at an ortho position with respect to a bond with the nitrogen (N). 14.The organic photoelectric device of claim 12, wherein the compoundrepresented by Chemical Formula 1 is represented by Chemical Formula 2:

wherein, in Chemical Formula 2, Ar is selected from a substituted orunsubstituted 5-membered aromatic ring, a substituted or unsubstituted6-membered aromatic ring, and a condensed ring of two or more of theforegoing rings, X¹ is Se, each of R¹ to R³ are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, each of R^(4a) to R^(4e) areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C₃ to C₃₀ heteroaryl group, a halogen, acyano group (—CN), a cyano-containing group, and a combination thereof,or optionally two adjacent groups of R^(4a) to R^(4e) are linked witheach other to provide a 5-membered aromatic ring or a 6-memberedaromatic ring, a is an integer of 0 or 1, X² is nitrogen (N), and Ar′¹is a heteroaryl group including at least one nitrogen (N) at an orthoposition with respect to a bond with the nitrogen (N).
 15. The organicphotoelectric device of claim 14, wherein, in Chemical Formula 2, Ar′¹is selected from a substituted or unsubstituted pyrrolyl group, asubstituted or unsubstituted pyrazolyl group, a substituted orunsubstituted imidazolyl group, a substituted or unsubstituted oxazolylgroup, a substituted or unsubstituted isoxazolyl group, a substituted orunsubstituted thiazolyl group, a substituted or unsubstitutedisothiazolyl group, a substituted or unsubstituted pyridinyl group, asubstituted or unsubstituted pyridazinyl group, a substituted orunsubstituted pyrimidinyl group, a substituted or unsubstitutedpyrazinyl group, a substituted or unsubstituted indolyl group, asubstituted or unsubstituted quinolinyl group, a substituted orunsubstituted isoquinolinyl group, a substituted or unsubstitutednaphthyridinyl group, a substituted or unsubstituted cinnolinyl group, asubstituted or unsubstituted quinazolinyl group, a substituted orunsubstituted phthalazinyl group, a substituted or unsubstitutedbenzotriazinyl group, a substituted or unsubstituted pyridopyrazinylgroup, a substituted or unsubstituted pyridopyrimidinyl group, asubstituted or unsubstituted pyridopyridazinyl group, a substituted orunsubstituted thienyl group, a substituted or unsubstituted benzothienylgroup, a substituted or unsubstituted selenophenyl group, and asubstituted or unsubstituted benzoselenophenyl group.
 16. The organicphotoelectric device of claim 12, wherein the compound represented byChemical Formula 1 is represented by Chemical Formula 3:

wherein, in Chemical Formula 3, Ar is selected from a substituted orunsubstituted 5-membered aromatic ring, a substituted or unsubstituted6-membered aromatic ring, and a condensed ring of two or more of theforegoing rings, X¹ is Se, each of R¹ to R³ are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, each of R^(4a) to R^(4e) or R^(5a) toR^(5d) are independently selected from hydrogen, a substituted orunsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstituted C₁to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, or optionally two adjacent groups of R^(4a) toR^(4e) are linked with each other to provide a 5-membered aromatic ringor a 6-membered aromatic ring and optionally two adjacent groups ofR^(5a) to R^(5d) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring, and each of a and b areindependently an integer of 0 or
 1. 17. The organic photoelectric deviceof claim 12, wherein, in Chemical Formula 1, a ring group represented byAr and bound to a methine group is represented by Chemical Formula 4:

wherein, in Chemical Formula 4, Ar′ is selected from a substituted orunsubstituted 5-membered aromatic ring, a substituted or unsubstituted6-membered aromatic ring, and a condensed ring of two or more of theforegoing rings, Z¹ is O or CR^(b)R^(c), wherein each of R^(b) and R^(c)are independently selected from hydrogen, a substituted or unsubstitutedC₁ to C₁₀ alkyl group, a cyano group, or a cyano-containing group,provided that at least one of R^(b) and R^(c) is a cyano group or acyano-containing group.
 18. The organic photoelectric device of claim12, wherein a ring group represented by Ar and bound to a methine groupis a cyclic group represented by one of Chemical Formulae 5-1 to 5-4:

wherein, in Chemical Formula 5-1, Z¹ is O or CR^(b)R^(c), wherein eachof R^(b) and R^(c) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₁₀ alkyl group, a cyano group, or acyano-containing group, provided that at least one of R^(b) and R^(c) isa cyano group or a cyano-containing group, Y¹ is selected from N andCR^(d), wherein R^(d) is selected from hydrogen and a substituted orunsubstituted C₁ to C₁₀ alkyl group, each of R¹¹, R¹², R¹³, R¹⁴, and R¹⁵are independently selected from hydrogen, a substituted or unsubstitutedC₁ to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C₄ to C₃₀ heteroaryl group, a halogen, acyano group (—CN), a cyano-containing group, and a combination thereof,or R¹² and R¹³ are independently linked with each other to provide anaromatic ring and R¹⁴ and R¹⁵ are independently linked with each otherto provide an aromatic ring, m1 is 0 or 1, and n is 0 or 1,

wherein, in Chemical Formula 5-2, Y² is selected from O, S, Se, Te, andC(R^(e))(CN) wherein R^(e) is selected from hydrogen, a cyano group(—CN), and a C₁ to C₁₀ alkyl group, and each of R¹⁶ and R¹⁷ areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C4 to C₃₀ heteroaryl group, a halogen, acyano group (—CN), and a combination thereof,

wherein, in Chemical Formula 5-3, each of R¹⁸ to R²⁰ are independentlyselected from hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkylgroup, a substituted or unsubstituted C₁ to C₃₀ alkoxy group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C4 to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof,

wherein, in Chemical Formula 5-4, Y³ is selected from O, S, Se, and Te,Y⁴ is N or NR^(f), Y⁵ is selected from CR^(g), C═O, C═S, C═(CR^(h))(CN),and Chemical Formula 5-4, at least one of Y² and Y⁵ is C═O, each ofR^(f), R^(g) and R^(h) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, and optionally Y⁴ and Y⁵ are linked with each otherto provide a fused ring with a Y⁴-Y⁵-containing pentagonal ring ofChemical Formula 5-4.
 19. The organic photoelectric device of claim 12,wherein the compound represented by Chemical Formula 1 is a compoundrepresented by one of Chemical Formulae 6-1 to 6-4:

wherein, in Chemical Formula 6-1, X¹ is Se, each of R¹ to R³ areindependently selected from hydrogen, a substituted or unsubstituted C₁to C₃₀ alkyl group, a substituted or unsubstituted C₁ to C₃₀ alkoxygroup, a substituted or unsubstituted C₆ to C₃₀ aryl group, asubstituted or unsubstituted C₃ to C₃₀ heteroaryl group, a halogen, acyano group (—CN), a cyano-containing group, and a combination thereof,Z¹ is O or CR^(b)R^(c), wherein R^(b) and R^(c) are independentlyselected from hydrogen, a substituted or unsubstituted C₁ to C₁₀ alkylgroup, a cyano group, or a cyano-containing group, provided that atleast one of R^(b) and R^(c) is a cyano group or a cyano-containinggroup, Y¹ is selected from N and CR^(d), wherein R^(d) is selected fromhydrogen and a substituted or unsubstituted C₁ to C₁₀ alkyl group, eachof R¹¹, R¹², R¹³, R¹⁴, and R¹⁵ are independently selected from hydrogen,a substituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), a cyano-containing group, and acombination thereof or R¹² and R¹³ are independently linked with eachother to provide an aromatic ring and R¹⁴ and R¹⁵ are independentlylinked with each other to provide an aromatic ring, m1 is 0 or 1, n is 0or 1, each of R^(4a) to R^(4e) are independently selected from hydrogen,a substituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C₃ to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, or optionally two adjacent groups of R^(4a) toR^(4e) are linked with each other to provide a 5-membered aromatic ringor a 6-membered aromatic ring, and a is an integer of 0 or 1,

wherein, in Chemical Formula 6-2, X¹ is Se, Y² is selected from O, S,Se, Te, and C(R^(e))(CN) wherein R^(e) is selected from hydrogen, acyano group (—CN), and a C₁ to C₁₀ alkyl group, each of R¹, R², R³, R¹⁶,and R¹⁷ are independently selected from hydrogen, a substituted orunsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstituted C₁to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C4 to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, each of R^(4a) to R^(4e) are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring, and a is an integer of 0 or1,

wherein, in Chemical Formula 6-3, X¹ is Se, each of R¹, R², R³, R¹⁸,R¹⁹, and R²⁰ are independently selected from hydrogen, a substituted orunsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstituted C₁to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C4 to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, each of R^(4a) to R^(4e) are independently selectedfrom hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkyl group, asubstituted or unsubstituted C₁ to C₃₀ alkoxy group, a substituted orunsubstituted C₆ to C₃₀ aryl group, a substituted or unsubstituted C₃ toC₃₀ heteroaryl group, a halogen, a cyano group (—CN), a cyano-containinggroup, and a combination thereof, or optionally two adjacent groups ofR^(4a) to R^(4e) are linked with each other to provide a 5-memberedaromatic ring or a 6-membered aromatic ring, and a is an integer of 0 or1,

wherein, in Chemical Formula 6-4, X¹ is Se, Y² is selected from O, S,Se, Te, and C(R^(e))(CN) wherein R^(e) is selected from hydrogen, acyano group (—CN), and a C₁ to C₁₀ alkyl group, Y³ is selected from O,S, Se, and Te, Y⁴ is N or NR^(f), Y⁵ is selected from CR^(g), C═O, C═S,C═(CR^(h))(CN), and Chemical Formula 5-4, at least one of Y² and Y⁵ isC═O, each of R¹, R², R³, R^(f), R^(g), and R^(h) are independentlyselected from hydrogen, a substituted or unsubstituted C₁ to C₃₀ alkylgroup, a substituted or unsubstituted C₁ to C₃₀ alkoxy group, asubstituted or unsubstituted C₆ to C₃₀ aryl group, a substituted orunsubstituted C4 to C₃₀ heteroaryl group, a halogen, a cyano group(—CN), a cyano-containing group, and a combination thereof, optionallyY⁴ and Y⁵ are linked with each other to provide a fused ring with aY⁴-Y⁵-containing pentagonal ring of Chemical Formula 5-4, each of R^(4a)to R^(4e) are independently selected from hydrogen, a substituted orunsubstituted C₁ to C₃₀ alkyl group, a substituted or unsubstituted C₁to C₃₀ alkoxy group, a substituted or unsubstituted C₆ to C₃₀ arylgroup, a substituted or unsubstituted C₃ to C₃₀ heteroaryl group, ahalogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, or optionally two adjacent groups of R^(4a) toR^(4e) are linked with each other to provide a 5-membered aromatic ringor a 6-membered aromatic ring, and a is an integer of 0 or 1,

wherein, in Chemical Formula 5-4, Y³ is selected from O, S, Se, and Te,Y⁴ is N or NR^(f), Y⁵ is selected from CR^(g), C═O, C═S, C═(CR^(h))(CN),and Chemical Formula 5-4, at least one of Y² and Y⁵ is C═O, each ofR^(f), R^(g), and R^(h) are independently selected from hydrogen, asubstituted or unsubstituted C₁ to C₃₀ alkyl group, a substituted orunsubstituted C₁ to C₃₀ alkoxy group, a substituted or unsubstituted C₆to C₃₀ aryl group, a substituted or unsubstituted C4 to C₃₀ heteroarylgroup, a halogen, a cyano group (—CN), a cyano-containing group, and acombination thereof, and optionally Y⁴ and Y⁵ are linked with each otherto provide a fused ring with a Y⁴-Y⁵-containing pentagonal ring ofChemical Formula 5-4.
 20. The organic photoelectric device of claim 12,wherein the active layer has a maximum absorption wavelength (λ_(max))in a wavelength region of greater than or equal to about 510 nm and lessthan about 560 nm.
 21. The organic photoelectric device of claim 12,wherein the active layer has a maximum absorption wavelength (λ_(max))in a wavelength region of about 520 nm to about 555 nm.
 22. The organicphotoelectric device of claim 12, wherein the active layer exhibits alight absorption curve having a full width at half maximum (FWHM) ofabout 50 nm to about 110 nm.
 23. The organic photoelectric device ofclaim 12, wherein the active layer has have an absorption coefficient ofgreater than or equal to about 5.5×10⁴ cm⁻¹, when including the compoundChemical Formula 1 and C60 in a volume ratio of about 0.9:1 to about1.1:1.
 24. The organic photoelectric device of claim 12, wherein theactive layer has have an absorption coefficient of about 5.8×10⁴ cm⁻¹ toabout 10×10⁴ cm⁻¹, when including the compound Chemical Formula 1 andC60 in a volume ratio of about 0.9:1 to about 1.1:1.
 25. An image sensorcomprising the organic photoelectric device of claim
 12. 26. The imagesensor of claim 25, wherein the image sensor includes a semiconductorsubstrate integrated with a plurality of first photo-sensing devicessensing light in a blue wavelength region and a plurality of secondphoto-sensing devices sensing light in a red wavelength region, and theorganic photoelectric device on the semiconductor substrate andselectively sensing light in a green wavelength region.
 27. The imagesensor of claim 26, wherein the image sensor further includes a colorfilter layer between the semiconductor substrate and the organicphotoelectric device, and including a blue filter selectively absorbinglight in a blue wavelength region and a red filter selectively absorbinglight in a red wavelength region.
 28. The image sensor of claim 26,wherein the first photo-sensing device and the second photo-sensingdevice are stacked in a vertical direction in the semiconductorsubstrate.
 29. The image sensor of claim 25, wherein the image sensorincludes a green photoelectric device of the organic photoelectricdevice, a blue photoelectric device selectively absorbing light in ablue wavelength region, and a red photoelectric device selectivelyabsorbing light in a red wavelength region that are stacked.
 30. Theimage sensor of claim 25, wherein the image sensor has a colordifference (ΔE*ab) of less than about 4.0.
 31. An electronic devicecomprising the image sensor of claim 25.